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      1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
      2 // Use of this source code is governed by a BSD-style license that can be
      3 // found in the LICENSE file.
      4 
      5 #include "content/browser/browser_main_loop.h"
      6 
      7 #include "base/bind.h"
      8 #include "base/command_line.h"
      9 #include "base/debug/trace_event.h"
     10 #include "base/file_util.h"
     11 #include "base/logging.h"
     12 #include "base/message_loop/message_loop.h"
     13 #include "base/metrics/field_trial.h"
     14 #include "base/metrics/histogram.h"
     15 #include "base/path_service.h"
     16 #include "base/pending_task.h"
     17 #include "base/power_monitor/power_monitor.h"
     18 #include "base/power_monitor/power_monitor_device_source.h"
     19 #include "base/process/process_metrics.h"
     20 #include "base/run_loop.h"
     21 #include "base/strings/string_number_conversions.h"
     22 #include "base/system_monitor/system_monitor.h"
     23 #include "base/thread_task_runner_handle.h"
     24 #include "base/threading/thread_restrictions.h"
     25 #include "base/timer/hi_res_timer_manager.h"
     26 #include "content/browser/battery_status/battery_status_service.h"
     27 #include "content/browser/browser_thread_impl.h"
     28 #include "content/browser/device_sensors/device_inertial_sensor_service.h"
     29 #include "content/browser/download/save_file_manager.h"
     30 #include "content/browser/gamepad/gamepad_service.h"
     31 #include "content/browser/gpu/browser_gpu_channel_host_factory.h"
     32 #include "content/browser/gpu/compositor_util.h"
     33 #include "content/browser/gpu/gpu_data_manager_impl.h"
     34 #include "content/browser/gpu/gpu_process_host.h"
     35 #include "content/browser/gpu/gpu_process_host_ui_shim.h"
     36 #include "content/browser/histogram_synchronizer.h"
     37 #include "content/browser/loader/resource_dispatcher_host_impl.h"
     38 #include "content/browser/media/capture/audio_mirroring_manager.h"
     39 #include "content/browser/media/media_internals.h"
     40 #include "content/browser/net/browser_online_state_observer.h"
     41 #include "content/browser/plugin_service_impl.h"
     42 #include "content/browser/renderer_host/media/media_stream_manager.h"
     43 #include "content/browser/speech/speech_recognition_manager_impl.h"
     44 #include "content/browser/startup_task_runner.h"
     45 #include "content/browser/time_zone_monitor.h"
     46 #include "content/browser/webui/content_web_ui_controller_factory.h"
     47 #include "content/browser/webui/url_data_manager.h"
     48 #include "content/public/browser/browser_main_parts.h"
     49 #include "content/public/browser/browser_shutdown.h"
     50 #include "content/public/browser/content_browser_client.h"
     51 #include "content/public/browser/render_process_host.h"
     52 #include "content/public/browser/tracing_controller.h"
     53 #include "content/public/common/content_switches.h"
     54 #include "content/public/common/main_function_params.h"
     55 #include "content/public/common/result_codes.h"
     56 #include "crypto/nss_util.h"
     57 #include "media/audio/audio_manager.h"
     58 #include "media/base/media.h"
     59 #include "media/base/user_input_monitor.h"
     60 #include "media/midi/midi_manager.h"
     61 #include "net/base/network_change_notifier.h"
     62 #include "net/socket/client_socket_factory.h"
     63 #include "net/ssl/ssl_config_service.h"
     64 #include "ui/base/clipboard/clipboard.h"
     65 
     66 #if defined(USE_AURA) || (defined(OS_MACOSX) && !defined(OS_IOS))
     67 #include "content/browser/compositor/image_transport_factory.h"
     68 #endif
     69 
     70 #if defined(USE_AURA)
     71 #include "content/public/browser/context_factory.h"
     72 #include "ui/aura/env.h"
     73 #endif
     74 
     75 #if !defined(OS_IOS)
     76 #include "content/browser/renderer_host/render_process_host_impl.h"
     77 #endif
     78 
     79 #if defined(OS_ANDROID)
     80 #include "base/android/jni_android.h"
     81 #include "content/browser/android/browser_startup_controller.h"
     82 #include "content/browser/android/surface_texture_peer_browser_impl.h"
     83 #include "content/browser/android/tracing_controller_android.h"
     84 #include "ui/gl/gl_surface.h"
     85 #endif
     86 
     87 #if defined(OS_MACOSX) && !defined(OS_IOS)
     88 #include "content/browser/bootstrap_sandbox_mac.h"
     89 #include "content/browser/theme_helper_mac.h"
     90 #endif
     91 
     92 #if defined(OS_WIN)
     93 #include <windows.h>
     94 #include <commctrl.h>
     95 #include <shellapi.h>
     96 
     97 #include "content/browser/system_message_window_win.h"
     98 #include "content/common/sandbox_win.h"
     99 #include "net/base/winsock_init.h"
    100 #include "ui/base/l10n/l10n_util_win.h"
    101 #endif
    102 
    103 #if defined(USE_GLIB)
    104 #include <glib-object.h>
    105 #endif
    106 
    107 #if defined(OS_LINUX) && defined(USE_UDEV)
    108 #include "content/browser/device_monitor_udev.h"
    109 #elif defined(OS_MACOSX) && !defined(OS_IOS)
    110 #include "content/browser/device_monitor_mac.h"
    111 #endif
    112 
    113 #if defined(OS_POSIX) && !defined(OS_MACOSX)
    114 #include "content/browser/renderer_host/render_sandbox_host_linux.h"
    115 #include "content/browser/zygote_host/zygote_host_impl_linux.h"
    116 #include "sandbox/linux/suid/client/setuid_sandbox_client.h"
    117 #endif
    118 
    119 #if defined(TCMALLOC_TRACE_MEMORY_SUPPORTED)
    120 #include "third_party/tcmalloc/chromium/src/gperftools/heap-profiler.h"
    121 #endif
    122 
    123 #if defined(USE_X11)
    124 #include "ui/gfx/x/x11_connection.h"
    125 #include "ui/gfx/x/x11_types.h"
    126 #endif
    127 
    128 // One of the linux specific headers defines this as a macro.
    129 #ifdef DestroyAll
    130 #undef DestroyAll
    131 #endif
    132 
    133 namespace content {
    134 namespace {
    135 
    136 #if defined(OS_POSIX) && !defined(OS_MACOSX) && !defined(OS_ANDROID)
    137 void SetupSandbox(const CommandLine& parsed_command_line) {
    138   TRACE_EVENT0("startup", "SetupSandbox");
    139   base::FilePath sandbox_binary;
    140 
    141   scoped_ptr<sandbox::SetuidSandboxClient> setuid_sandbox_client(
    142       sandbox::SetuidSandboxClient::Create());
    143 
    144   const bool want_setuid_sandbox =
    145       !parsed_command_line.HasSwitch(switches::kNoSandbox) &&
    146       !parsed_command_line.HasSwitch(switches::kDisableSetuidSandbox) &&
    147       !setuid_sandbox_client->IsDisabledViaEnvironment();
    148 
    149   static const char no_suid_error[] =
    150       "Running without the SUID sandbox! See "
    151       "https://code.google.com/p/chromium/wiki/LinuxSUIDSandboxDevelopment "
    152       "for more information on developing with the sandbox on.";
    153   if (want_setuid_sandbox) {
    154     sandbox_binary = setuid_sandbox_client->GetSandboxBinaryPath();
    155     if (sandbox_binary.empty()) {
    156       // This needs to be fatal. Talk to security (at) chromium.org if you feel
    157       // otherwise.
    158       LOG(FATAL) << no_suid_error;
    159     }
    160   } else {
    161     LOG(ERROR) << no_suid_error;
    162   }
    163 
    164   // Tickle the sandbox host and zygote host so they fork now.
    165   RenderSandboxHostLinux::GetInstance()->Init();
    166   ZygoteHostImpl::GetInstance()->Init(sandbox_binary.value());
    167 }
    168 #endif
    169 
    170 #if defined(USE_GLIB)
    171 static void GLibLogHandler(const gchar* log_domain,
    172                            GLogLevelFlags log_level,
    173                            const gchar* message,
    174                            gpointer userdata) {
    175   if (!log_domain)
    176     log_domain = "<unknown>";
    177   if (!message)
    178     message = "<no message>";
    179 
    180   if (strstr(message, "Unable to retrieve the file info for")) {
    181     LOG(ERROR) << "GTK File code error: " << message;
    182   } else if (strstr(message, "Could not find the icon") &&
    183              strstr(log_domain, "Gtk")) {
    184     LOG(ERROR) << "GTK icon error: " << message;
    185   } else if (strstr(message, "Theme file for default has no") ||
    186              strstr(message, "Theme directory") ||
    187              strstr(message, "theme pixmap") ||
    188              strstr(message, "locate theme engine")) {
    189     LOG(ERROR) << "GTK theme error: " << message;
    190   } else if (strstr(message, "Unable to create Ubuntu Menu Proxy") &&
    191              strstr(log_domain, "<unknown>")) {
    192     LOG(ERROR) << "GTK menu proxy create failed";
    193   } else if (strstr(message, "Out of memory") &&
    194              strstr(log_domain, "<unknown>")) {
    195     LOG(ERROR) << "DBus call timeout or out of memory: "
    196                << "http://crosbug.com/15496";
    197   } else if (strstr(message, "Could not connect: Connection refused") &&
    198              strstr(log_domain, "<unknown>")) {
    199     LOG(ERROR) << "DConf settings backend could not connect to session bus: "
    200                << "http://crbug.com/179797";
    201   } else if (strstr(message, "Attempting to store changes into") ||
    202              strstr(message, "Attempting to set the permissions of")) {
    203     LOG(ERROR) << message << " (http://bugs.chromium.org/161366)";
    204   } else if (strstr(message, "drawable is not a native X11 window")) {
    205     LOG(ERROR) << message << " (http://bugs.chromium.org/329991)";
    206   } else {
    207     LOG(DFATAL) << log_domain << ": " << message;
    208   }
    209 }
    210 
    211 static void SetUpGLibLogHandler() {
    212   // Register GLib-handled assertions to go through our logging system.
    213   const char* kLogDomains[] = { NULL, "Gtk", "Gdk", "GLib", "GLib-GObject" };
    214   for (size_t i = 0; i < arraysize(kLogDomains); i++) {
    215     g_log_set_handler(kLogDomains[i],
    216                       static_cast<GLogLevelFlags>(G_LOG_FLAG_RECURSION |
    217                                                   G_LOG_FLAG_FATAL |
    218                                                   G_LOG_LEVEL_ERROR |
    219                                                   G_LOG_LEVEL_CRITICAL |
    220                                                   G_LOG_LEVEL_WARNING),
    221                       GLibLogHandler,
    222                       NULL);
    223   }
    224 }
    225 #endif
    226 
    227 void OnStoppedStartupTracing(const base::FilePath& trace_file) {
    228   VLOG(0) << "Completed startup tracing to " << trace_file.value();
    229 }
    230 
    231 #if defined(USE_AURA)
    232 bool ShouldInitializeBrowserGpuChannelAndTransportSurface() {
    233   return true;
    234 }
    235 #elif defined(OS_MACOSX) && !defined(OS_IOS)
    236 bool ShouldInitializeBrowserGpuChannelAndTransportSurface() {
    237   return IsDelegatedRendererEnabled();
    238 }
    239 #endif
    240 
    241 }  // namespace
    242 
    243 // The currently-running BrowserMainLoop.  There can be one or zero.
    244 BrowserMainLoop* g_current_browser_main_loop = NULL;
    245 
    246 // This is just to be able to keep ShutdownThreadsAndCleanUp out of
    247 // the public interface of BrowserMainLoop.
    248 class BrowserShutdownImpl {
    249  public:
    250   static void ImmediateShutdownAndExitProcess() {
    251     DCHECK(g_current_browser_main_loop);
    252     g_current_browser_main_loop->ShutdownThreadsAndCleanUp();
    253 
    254 #if defined(OS_WIN)
    255     // At this point the message loop is still running yet we've shut everything
    256     // down. If any messages are processed we'll likely crash. Exit now.
    257     ExitProcess(RESULT_CODE_NORMAL_EXIT);
    258 #elif defined(OS_POSIX) && !defined(OS_MACOSX)
    259     _exit(RESULT_CODE_NORMAL_EXIT);
    260 #else
    261     NOTIMPLEMENTED();
    262 #endif
    263   }
    264 };
    265 
    266 void ImmediateShutdownAndExitProcess() {
    267   BrowserShutdownImpl::ImmediateShutdownAndExitProcess();
    268 }
    269 
    270 // For measuring memory usage after each task. Behind a command line flag.
    271 class BrowserMainLoop::MemoryObserver : public base::MessageLoop::TaskObserver {
    272  public:
    273   MemoryObserver() {}
    274   virtual ~MemoryObserver() {}
    275 
    276   virtual void WillProcessTask(const base::PendingTask& pending_task) OVERRIDE {
    277   }
    278 
    279   virtual void DidProcessTask(const base::PendingTask& pending_task) OVERRIDE {
    280 #if !defined(OS_IOS)  // No ProcessMetrics on IOS.
    281     scoped_ptr<base::ProcessMetrics> process_metrics(
    282         base::ProcessMetrics::CreateProcessMetrics(
    283 #if defined(OS_MACOSX)
    284             base::GetCurrentProcessHandle(), NULL));
    285 #else
    286             base::GetCurrentProcessHandle()));
    287 #endif
    288     size_t private_bytes;
    289     process_metrics->GetMemoryBytes(&private_bytes, NULL);
    290     HISTOGRAM_MEMORY_KB("Memory.BrowserUsed", private_bytes >> 10);
    291 #endif
    292   }
    293  private:
    294   DISALLOW_COPY_AND_ASSIGN(MemoryObserver);
    295 };
    296 
    297 
    298 // BrowserMainLoop construction / destruction =============================
    299 
    300 BrowserMainLoop* BrowserMainLoop::GetInstance() {
    301   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
    302   return g_current_browser_main_loop;
    303 }
    304 
    305 BrowserMainLoop::BrowserMainLoop(const MainFunctionParams& parameters)
    306     : parameters_(parameters),
    307       parsed_command_line_(parameters.command_line),
    308       result_code_(RESULT_CODE_NORMAL_EXIT),
    309       created_threads_(false),
    310       // ContentMainRunner should have enabled tracing of the browser process
    311       // when kTraceStartup is in the command line.
    312       is_tracing_startup_(
    313           parameters.command_line.HasSwitch(switches::kTraceStartup)) {
    314   DCHECK(!g_current_browser_main_loop);
    315   g_current_browser_main_loop = this;
    316 }
    317 
    318 BrowserMainLoop::~BrowserMainLoop() {
    319   DCHECK_EQ(this, g_current_browser_main_loop);
    320 #if !defined(OS_IOS)
    321   ui::Clipboard::DestroyClipboardForCurrentThread();
    322 #endif  // !defined(OS_IOS)
    323   g_current_browser_main_loop = NULL;
    324 }
    325 
    326 void BrowserMainLoop::Init() {
    327   TRACE_EVENT0("startup", "BrowserMainLoop::Init");
    328   parts_.reset(
    329       GetContentClient()->browser()->CreateBrowserMainParts(parameters_));
    330 }
    331 
    332 // BrowserMainLoop stages ==================================================
    333 
    334 void BrowserMainLoop::EarlyInitialization() {
    335   TRACE_EVENT0("startup", "BrowserMainLoop::EarlyInitialization");
    336 
    337 #if defined(OS_POSIX) && !defined(OS_MACOSX) && !defined(OS_ANDROID)
    338   // No thread should be created before this call, as SetupSandbox()
    339   // will end-up using fork().
    340   SetupSandbox(parsed_command_line_);
    341 #endif
    342 
    343 #if defined(USE_X11)
    344   if (parsed_command_line_.HasSwitch(switches::kSingleProcess) ||
    345       parsed_command_line_.HasSwitch(switches::kInProcessGPU)) {
    346     if (!gfx::InitializeThreadedX11()) {
    347       LOG(ERROR) << "Failed to put Xlib into threaded mode.";
    348     }
    349   }
    350 #endif
    351 
    352   // GLib's spawning of new processes is buggy, so it's important that at this
    353   // point GLib does not need to start DBUS. Chrome should always start with
    354   // DBUS_SESSION_BUS_ADDRESS properly set. See crbug.com/309093.
    355 #if defined(USE_GLIB)
    356   // g_type_init will be deprecated in 2.36. 2.35 is the development
    357   // version for 2.36, hence do not call g_type_init starting 2.35.
    358   // http://developer.gnome.org/gobject/unstable/gobject-Type-Information.html#g-type-init
    359 #if !GLIB_CHECK_VERSION(2, 35, 0)
    360   // GLib type system initialization. Needed at least for gconf,
    361   // used in net/proxy/proxy_config_service_linux.cc. Most likely
    362   // this is superfluous as gtk_init() ought to do this. It's
    363   // definitely harmless, so retained as a reminder of this
    364   // requirement for gconf.
    365   g_type_init();
    366 #endif
    367 
    368   SetUpGLibLogHandler();
    369 #endif
    370 
    371   if (parts_)
    372     parts_->PreEarlyInitialization();
    373 
    374 #if defined(OS_MACOSX)
    375   // We use quite a few file descriptors for our IPC, and the default limit on
    376   // the Mac is low (256), so bump it up.
    377   base::SetFdLimit(1024);
    378 #endif
    379 
    380 #if defined(OS_WIN)
    381   net::EnsureWinsockInit();
    382 #endif
    383 
    384 #if !defined(USE_OPENSSL)
    385   // We want to be sure to init NSPR on the main thread.
    386   crypto::EnsureNSPRInit();
    387 #endif  // !defined(USE_OPENSSL)
    388 
    389 #if !defined(OS_IOS)
    390   if (parsed_command_line_.HasSwitch(switches::kRendererProcessLimit)) {
    391     std::string limit_string = parsed_command_line_.GetSwitchValueASCII(
    392         switches::kRendererProcessLimit);
    393     size_t process_limit;
    394     if (base::StringToSizeT(limit_string, &process_limit)) {
    395       RenderProcessHost::SetMaxRendererProcessCount(process_limit);
    396     }
    397   }
    398 #endif  // !defined(OS_IOS)
    399 
    400   if (parts_)
    401     parts_->PostEarlyInitialization();
    402 }
    403 
    404 void BrowserMainLoop::MainMessageLoopStart() {
    405   TRACE_EVENT0("startup", "BrowserMainLoop::MainMessageLoopStart");
    406   if (parts_) {
    407     TRACE_EVENT0("startup",
    408         "BrowserMainLoop::MainMessageLoopStart:PreMainMessageLoopStart");
    409     parts_->PreMainMessageLoopStart();
    410   }
    411 
    412 #if defined(OS_WIN)
    413   // If we're running tests (ui_task is non-null), then the ResourceBundle
    414   // has already been initialized.
    415   if (!parameters_.ui_task) {
    416     // Override the configured locale with the user's preferred UI language.
    417     l10n_util::OverrideLocaleWithUILanguageList();
    418   }
    419 #endif
    420 
    421   // Create a MessageLoop if one does not already exist for the current thread.
    422   if (!base::MessageLoop::current())
    423     main_message_loop_.reset(new base::MessageLoopForUI);
    424 
    425   InitializeMainThread();
    426 
    427   {
    428     TRACE_EVENT0("startup", "BrowserMainLoop::Subsystem:SystemMonitor");
    429     system_monitor_.reset(new base::SystemMonitor);
    430   }
    431   {
    432     TRACE_EVENT0("startup", "BrowserMainLoop::Subsystem:PowerMonitor");
    433     scoped_ptr<base::PowerMonitorSource> power_monitor_source(
    434       new base::PowerMonitorDeviceSource());
    435     power_monitor_.reset(new base::PowerMonitor(power_monitor_source.Pass()));
    436   }
    437   {
    438     TRACE_EVENT0("startup", "BrowserMainLoop::Subsystem:HighResTimerManager");
    439     hi_res_timer_manager_.reset(new base::HighResolutionTimerManager);
    440   }
    441   {
    442     TRACE_EVENT0("startup", "BrowserMainLoop::Subsystem:NetworkChangeNotifier");
    443     network_change_notifier_.reset(net::NetworkChangeNotifier::Create());
    444   }
    445 
    446 #if !defined(OS_IOS)
    447   {
    448     TRACE_EVENT0("startup", "BrowserMainLoop::Subsystem:MediaFeatures");
    449     media::InitializeCPUSpecificMediaFeatures();
    450   }
    451   {
    452     TRACE_EVENT0("startup", "BrowserMainLoop::Subsystem:AudioMan");
    453     audio_manager_.reset(media::AudioManager::Create(
    454         MediaInternals::GetInstance()));
    455   }
    456   {
    457     TRACE_EVENT0("startup", "BrowserMainLoop::Subsystem:MidiManager");
    458     midi_manager_.reset(media::MidiManager::Create());
    459   }
    460   {
    461     TRACE_EVENT0("startup",
    462                  "BrowserMainLoop::Subsystem:ContentWebUIController");
    463     WebUIControllerFactory::RegisterFactory(
    464         ContentWebUIControllerFactory::GetInstance());
    465   }
    466 
    467   {
    468     TRACE_EVENT0("startup", "BrowserMainLoop::Subsystem:AudioMirroringManager");
    469     audio_mirroring_manager_.reset(new AudioMirroringManager());
    470   }
    471   {
    472     TRACE_EVENT0("startup", "BrowserMainLoop::Subsystem:OnlineStateObserver");
    473     online_state_observer_.reset(new BrowserOnlineStateObserver);
    474   }
    475 
    476   {
    477     system_stats_monitor_.reset(new base::debug::TraceEventSystemStatsMonitor(
    478         base::ThreadTaskRunnerHandle::Get()));
    479   }
    480 #endif  // !defined(OS_IOS)
    481 
    482 #if defined(OS_WIN)
    483   system_message_window_.reset(new SystemMessageWindowWin);
    484 #endif
    485 
    486   if (parts_)
    487     parts_->PostMainMessageLoopStart();
    488 
    489 #if !defined(OS_IOS)
    490   // Start tracing to a file if needed. Only do this after starting the main
    491   // message loop to avoid calling MessagePumpForUI::ScheduleWork() before
    492   // MessagePumpForUI::Start() as it will crash the browser.
    493   if (is_tracing_startup_) {
    494     TRACE_EVENT0("startup", "BrowserMainLoop::InitStartupTracing");
    495     InitStartupTracing(parsed_command_line_);
    496   }
    497 #endif  // !defined(OS_IOS)
    498 
    499 #if defined(OS_ANDROID)
    500   {
    501     TRACE_EVENT0("startup", "BrowserMainLoop::Subsystem:SurfaceTexturePeer");
    502     SurfaceTexturePeer::InitInstance(new SurfaceTexturePeerBrowserImpl());
    503   }
    504 #endif
    505 
    506   if (parsed_command_line_.HasSwitch(switches::kMemoryMetrics)) {
    507     TRACE_EVENT0("startup", "BrowserMainLoop::Subsystem:MemoryObserver");
    508     memory_observer_.reset(new MemoryObserver());
    509     base::MessageLoop::current()->AddTaskObserver(memory_observer_.get());
    510   }
    511 
    512 #if defined(TCMALLOC_TRACE_MEMORY_SUPPORTED)
    513   trace_memory_controller_.reset(new base::debug::TraceMemoryController(
    514       base::MessageLoop::current()->message_loop_proxy(),
    515       ::HeapProfilerWithPseudoStackStart,
    516       ::HeapProfilerStop,
    517       ::GetHeapProfile));
    518 #endif
    519 }
    520 
    521 int BrowserMainLoop::PreCreateThreads() {
    522   if (parts_) {
    523     TRACE_EVENT0("startup",
    524         "BrowserMainLoop::CreateThreads:PreCreateThreads");
    525     result_code_ = parts_->PreCreateThreads();
    526   }
    527 
    528 #if defined(ENABLE_PLUGINS)
    529   // Prior to any processing happening on the io thread, we create the
    530   // plugin service as it is predominantly used from the io thread,
    531   // but must be created on the main thread. The service ctor is
    532   // inexpensive and does not invoke the io_thread() accessor.
    533   {
    534     TRACE_EVENT0("startup", "BrowserMainLoop::CreateThreads:PluginService");
    535     PluginService::GetInstance()->Init();
    536   }
    537 #endif
    538 
    539 #if !defined(OS_IOS) && (!defined(GOOGLE_CHROME_BUILD) || defined(OS_ANDROID))
    540   // Single-process is an unsupported and not fully tested mode, so
    541   // don't enable it for official Chrome builds (except on Android).
    542   if (parsed_command_line_.HasSwitch(switches::kSingleProcess))
    543     RenderProcessHost::SetRunRendererInProcess(true);
    544 #endif
    545   return result_code_;
    546 }
    547 
    548 void BrowserMainLoop::CreateStartupTasks() {
    549   TRACE_EVENT0("startup", "BrowserMainLoop::CreateStartupTasks");
    550 
    551   // First time through, we really want to create all the tasks
    552   if (!startup_task_runner_.get()) {
    553 #if defined(OS_ANDROID)
    554     startup_task_runner_ = make_scoped_ptr(new StartupTaskRunner(
    555         base::Bind(&BrowserStartupComplete),
    556         base::MessageLoop::current()->message_loop_proxy()));
    557 #else
    558     startup_task_runner_ = make_scoped_ptr(new StartupTaskRunner(
    559         base::Callback<void(int)>(),
    560         base::MessageLoop::current()->message_loop_proxy()));
    561 #endif
    562     StartupTask pre_create_threads =
    563         base::Bind(&BrowserMainLoop::PreCreateThreads, base::Unretained(this));
    564     startup_task_runner_->AddTask(pre_create_threads);
    565 
    566     StartupTask create_threads =
    567         base::Bind(&BrowserMainLoop::CreateThreads, base::Unretained(this));
    568     startup_task_runner_->AddTask(create_threads);
    569 
    570     StartupTask browser_thread_started = base::Bind(
    571         &BrowserMainLoop::BrowserThreadsStarted, base::Unretained(this));
    572     startup_task_runner_->AddTask(browser_thread_started);
    573 
    574     StartupTask pre_main_message_loop_run = base::Bind(
    575         &BrowserMainLoop::PreMainMessageLoopRun, base::Unretained(this));
    576     startup_task_runner_->AddTask(pre_main_message_loop_run);
    577 
    578 #if defined(OS_ANDROID)
    579     if (BrowserMayStartAsynchronously()) {
    580       startup_task_runner_->StartRunningTasksAsync();
    581     }
    582 #endif
    583   }
    584 #if defined(OS_ANDROID)
    585   if (!BrowserMayStartAsynchronously()) {
    586     // A second request for asynchronous startup can be ignored, so
    587     // StartupRunningTasksAsync is only called first time through. If, however,
    588     // this is a request for synchronous startup then it must override any
    589     // previous call for async startup, so we call RunAllTasksNow()
    590     // unconditionally.
    591     startup_task_runner_->RunAllTasksNow();
    592   }
    593 #else
    594   startup_task_runner_->RunAllTasksNow();
    595 #endif
    596 }
    597 
    598 int BrowserMainLoop::CreateThreads() {
    599   TRACE_EVENT0("startup", "BrowserMainLoop::CreateThreads");
    600 
    601   base::Thread::Options default_options;
    602   base::Thread::Options io_message_loop_options;
    603   io_message_loop_options.message_loop_type = base::MessageLoop::TYPE_IO;
    604   base::Thread::Options ui_message_loop_options;
    605   ui_message_loop_options.message_loop_type = base::MessageLoop::TYPE_UI;
    606 
    607   // Start threads in the order they occur in the BrowserThread::ID
    608   // enumeration, except for BrowserThread::UI which is the main
    609   // thread.
    610   //
    611   // Must be size_t so we can increment it.
    612   for (size_t thread_id = BrowserThread::UI + 1;
    613        thread_id < BrowserThread::ID_COUNT;
    614        ++thread_id) {
    615     scoped_ptr<BrowserProcessSubThread>* thread_to_start = NULL;
    616     base::Thread::Options* options = &default_options;
    617 
    618     switch (thread_id) {
    619       case BrowserThread::DB:
    620         TRACE_EVENT_BEGIN1("startup",
    621             "BrowserMainLoop::CreateThreads:start",
    622             "Thread", "BrowserThread::DB");
    623         thread_to_start = &db_thread_;
    624         break;
    625       case BrowserThread::FILE_USER_BLOCKING:
    626         TRACE_EVENT_BEGIN1("startup",
    627             "BrowserMainLoop::CreateThreads:start",
    628             "Thread", "BrowserThread::FILE_USER_BLOCKING");
    629         thread_to_start = &file_user_blocking_thread_;
    630         break;
    631       case BrowserThread::FILE:
    632         TRACE_EVENT_BEGIN1("startup",
    633             "BrowserMainLoop::CreateThreads:start",
    634             "Thread", "BrowserThread::FILE");
    635         thread_to_start = &file_thread_;
    636 #if defined(OS_WIN)
    637         // On Windows, the FILE thread needs to be have a UI message loop
    638         // which pumps messages in such a way that Google Update can
    639         // communicate back to us.
    640         options = &ui_message_loop_options;
    641 #else
    642         options = &io_message_loop_options;
    643 #endif
    644         break;
    645       case BrowserThread::PROCESS_LAUNCHER:
    646         TRACE_EVENT_BEGIN1("startup",
    647             "BrowserMainLoop::CreateThreads:start",
    648             "Thread", "BrowserThread::PROCESS_LAUNCHER");
    649         thread_to_start = &process_launcher_thread_;
    650         break;
    651       case BrowserThread::CACHE:
    652         TRACE_EVENT_BEGIN1("startup",
    653             "BrowserMainLoop::CreateThreads:start",
    654             "Thread", "BrowserThread::CACHE");
    655         thread_to_start = &cache_thread_;
    656         options = &io_message_loop_options;
    657         break;
    658       case BrowserThread::IO:
    659         TRACE_EVENT_BEGIN1("startup",
    660             "BrowserMainLoop::CreateThreads:start",
    661             "Thread", "BrowserThread::IO");
    662         thread_to_start = &io_thread_;
    663         options = &io_message_loop_options;
    664         break;
    665       case BrowserThread::UI:
    666       case BrowserThread::ID_COUNT:
    667       default:
    668         NOTREACHED();
    669         break;
    670     }
    671 
    672     BrowserThread::ID id = static_cast<BrowserThread::ID>(thread_id);
    673 
    674     if (thread_to_start) {
    675       (*thread_to_start).reset(new BrowserProcessSubThread(id));
    676       (*thread_to_start)->StartWithOptions(*options);
    677     } else {
    678       NOTREACHED();
    679     }
    680 
    681     TRACE_EVENT_END0("startup", "BrowserMainLoop::CreateThreads:start");
    682   }
    683   created_threads_ = true;
    684   return result_code_;
    685 }
    686 
    687 int BrowserMainLoop::PreMainMessageLoopRun() {
    688   if (parts_) {
    689     TRACE_EVENT0("startup",
    690         "BrowserMainLoop::CreateThreads:PreMainMessageLoopRun");
    691     parts_->PreMainMessageLoopRun();
    692   }
    693 
    694   // If the UI thread blocks, the whole UI is unresponsive.
    695   // Do not allow disk IO from the UI thread.
    696   base::ThreadRestrictions::SetIOAllowed(false);
    697   base::ThreadRestrictions::DisallowWaiting();
    698   return result_code_;
    699 }
    700 
    701 void BrowserMainLoop::RunMainMessageLoopParts() {
    702   TRACE_EVENT_BEGIN_ETW("BrowserMain:MESSAGE_LOOP", 0, "");
    703 
    704   bool ran_main_loop = false;
    705   if (parts_)
    706     ran_main_loop = parts_->MainMessageLoopRun(&result_code_);
    707 
    708   if (!ran_main_loop)
    709     MainMessageLoopRun();
    710 
    711   TRACE_EVENT_END_ETW("BrowserMain:MESSAGE_LOOP", 0, "");
    712 }
    713 
    714 void BrowserMainLoop::ShutdownThreadsAndCleanUp() {
    715   if (!created_threads_) {
    716     // Called early, nothing to do
    717     return;
    718   }
    719   TRACE_EVENT0("shutdown", "BrowserMainLoop::ShutdownThreadsAndCleanUp");
    720 
    721   // Teardown may start in PostMainMessageLoopRun, and during teardown we
    722   // need to be able to perform IO.
    723   base::ThreadRestrictions::SetIOAllowed(true);
    724   BrowserThread::PostTask(
    725       BrowserThread::IO, FROM_HERE,
    726       base::Bind(base::IgnoreResult(&base::ThreadRestrictions::SetIOAllowed),
    727                  true));
    728 
    729 #if !defined(OS_IOS)
    730   if (RenderProcessHost::run_renderer_in_process())
    731     RenderProcessHostImpl::ShutDownInProcessRenderer();
    732 #endif
    733 
    734   if (parts_) {
    735     TRACE_EVENT0("shutdown",
    736                  "BrowserMainLoop::Subsystem:PostMainMessageLoopRun");
    737     parts_->PostMainMessageLoopRun();
    738   }
    739 
    740   trace_memory_controller_.reset();
    741   system_stats_monitor_.reset();
    742 
    743 #if !defined(OS_IOS)
    744   // Destroying the GpuProcessHostUIShims on the UI thread posts a task to
    745   // delete related objects on the GPU thread. This must be done before
    746   // stopping the GPU thread. The GPU thread will close IPC channels to renderer
    747   // processes so this has to happen before stopping the IO thread.
    748   {
    749     TRACE_EVENT0("shutdown", "BrowserMainLoop::Subsystem:GPUProcessHostShim");
    750     GpuProcessHostUIShim::DestroyAll();
    751   }
    752   // Cancel pending requests and prevent new requests.
    753   if (resource_dispatcher_host_) {
    754     TRACE_EVENT0("shutdown",
    755                  "BrowserMainLoop::Subsystem:ResourceDispatcherHost");
    756     resource_dispatcher_host_.get()->Shutdown();
    757   }
    758 
    759 #if defined(USE_AURA) || defined(OS_MACOSX)
    760   if (ShouldInitializeBrowserGpuChannelAndTransportSurface()) {
    761     TRACE_EVENT0("shutdown",
    762                  "BrowserMainLoop::Subsystem:ImageTransportFactory");
    763     ImageTransportFactory::Terminate();
    764   }
    765 #endif
    766 
    767 #if defined(OS_POSIX) && !defined(OS_MACOSX) && !defined(OS_ANDROID)
    768   ZygoteHostImpl::GetInstance()->TearDownAfterLastChild();
    769 #endif  // defined(OS_POSIX) && !defined(OS_MACOSX) && !defined(OS_ANDROID)
    770 
    771   // The device monitors are using |system_monitor_| as dependency, so delete
    772   // them before |system_monitor_| goes away.
    773   // On Mac and windows, the monitor needs to be destroyed on the same thread
    774   // as they were created. On Linux, the monitor will be deleted when IO thread
    775   // goes away.
    776 #if defined(OS_WIN)
    777   system_message_window_.reset();
    778 #elif defined(OS_MACOSX)
    779   device_monitor_mac_.reset();
    780 #endif
    781 #endif  // !defined(OS_IOS)
    782 
    783   // Must be size_t so we can subtract from it.
    784   for (size_t thread_id = BrowserThread::ID_COUNT - 1;
    785        thread_id >= (BrowserThread::UI + 1);
    786        --thread_id) {
    787     // Find the thread object we want to stop. Looping over all valid
    788     // BrowserThread IDs and DCHECKing on a missing case in the switch
    789     // statement helps avoid a mismatch between this code and the
    790     // BrowserThread::ID enumeration.
    791     //
    792     // The destruction order is the reverse order of occurrence in the
    793     // BrowserThread::ID list. The rationale for the order is as
    794     // follows (need to be filled in a bit):
    795     //
    796     //
    797     // - The IO thread is the only user of the CACHE thread.
    798     //
    799     // - The PROCESS_LAUNCHER thread must be stopped after IO in case
    800     //   the IO thread posted a task to terminate a process on the
    801     //   process launcher thread.
    802     //
    803     // - (Not sure why DB stops last.)
    804     switch (thread_id) {
    805       case BrowserThread::DB: {
    806           TRACE_EVENT0("shutdown", "BrowserMainLoop::Subsystem:DBThread");
    807           db_thread_.reset();
    808         }
    809         break;
    810       case BrowserThread::FILE_USER_BLOCKING: {
    811           TRACE_EVENT0("shutdown",
    812                        "BrowserMainLoop::Subsystem:FileUserBlockingThread");
    813           file_user_blocking_thread_.reset();
    814         }
    815         break;
    816       case BrowserThread::FILE: {
    817           TRACE_EVENT0("shutdown", "BrowserMainLoop::Subsystem:FileThread");
    818 #if !defined(OS_IOS)
    819           // Clean up state that lives on or uses the file_thread_ before
    820           // it goes away.
    821           if (resource_dispatcher_host_)
    822             resource_dispatcher_host_.get()->save_file_manager()->Shutdown();
    823 #endif  // !defined(OS_IOS)
    824           file_thread_.reset();
    825         }
    826         break;
    827       case BrowserThread::PROCESS_LAUNCHER: {
    828           TRACE_EVENT0("shutdown", "BrowserMainLoop::Subsystem:LauncherThread");
    829           process_launcher_thread_.reset();
    830         }
    831         break;
    832       case BrowserThread::CACHE: {
    833           TRACE_EVENT0("shutdown", "BrowserMainLoop::Subsystem:CacheThread");
    834           cache_thread_.reset();
    835         }
    836         break;
    837       case BrowserThread::IO: {
    838           TRACE_EVENT0("shutdown", "BrowserMainLoop::Subsystem:IOThread");
    839           io_thread_.reset();
    840         }
    841         break;
    842       case BrowserThread::UI:
    843       case BrowserThread::ID_COUNT:
    844       default:
    845         NOTREACHED();
    846         break;
    847     }
    848   }
    849 
    850 #if !defined(OS_IOS)
    851   {
    852     TRACE_EVENT0("shutdown", "BrowserMainLoop::Subsystem:IndexedDBThread");
    853     indexed_db_thread_.reset();
    854   }
    855 #endif
    856 
    857   // Close the blocking I/O pool after the other threads. Other threads such
    858   // as the I/O thread may need to schedule work like closing files or flushing
    859   // data during shutdown, so the blocking pool needs to be available. There
    860   // may also be slow operations pending that will blcok shutdown, so closing
    861   // it here (which will block until required operations are complete) gives
    862   // more head start for those operations to finish.
    863   {
    864     TRACE_EVENT0("shutdown", "BrowserMainLoop::Subsystem:ThreadPool");
    865     BrowserThreadImpl::ShutdownThreadPool();
    866   }
    867 
    868 #if !defined(OS_IOS)
    869   // Must happen after the IO thread is shutdown since this may be accessed from
    870   // it.
    871   {
    872     TRACE_EVENT0("shutdown", "BrowserMainLoop::Subsystem:GPUChannelFactory");
    873     if (BrowserGpuChannelHostFactory::instance())
    874       BrowserGpuChannelHostFactory::Terminate();
    875   }
    876 
    877   // Must happen after the I/O thread is shutdown since this class lives on the
    878   // I/O thread and isn't threadsafe.
    879   {
    880     TRACE_EVENT0("shutdown", "BrowserMainLoop::Subsystem:GamepadService");
    881     GamepadService::GetInstance()->Terminate();
    882   }
    883   {
    884     TRACE_EVENT0("shutdown", "BrowserMainLoop::Subsystem:SensorService");
    885     DeviceInertialSensorService::GetInstance()->Shutdown();
    886   }
    887   {
    888     TRACE_EVENT0("shutdown", "BrowserMainLoop::Subsystem:BatteryStatusService");
    889     BatteryStatusService::GetInstance()->Shutdown();
    890   }
    891   {
    892     TRACE_EVENT0("shutdown", "BrowserMainLoop::Subsystem:DeleteDataSources");
    893     URLDataManager::DeleteDataSources();
    894   }
    895 #endif  // !defined(OS_IOS)
    896 
    897   if (parts_) {
    898     TRACE_EVENT0("shutdown", "BrowserMainLoop::Subsystem:PostDestroyThreads");
    899     parts_->PostDestroyThreads();
    900   }
    901 }
    902 
    903 void BrowserMainLoop::InitializeMainThread() {
    904   TRACE_EVENT0("startup", "BrowserMainLoop::InitializeMainThread");
    905   const char* kThreadName = "CrBrowserMain";
    906   base::PlatformThread::SetName(kThreadName);
    907   if (main_message_loop_)
    908     main_message_loop_->set_thread_name(kThreadName);
    909 
    910   // Register the main thread by instantiating it, but don't call any methods.
    911   main_thread_.reset(
    912       new BrowserThreadImpl(BrowserThread::UI, base::MessageLoop::current()));
    913 }
    914 
    915 int BrowserMainLoop::BrowserThreadsStarted() {
    916   TRACE_EVENT0("startup", "BrowserMainLoop::BrowserThreadsStarted");
    917 
    918 #if !defined(OS_IOS)
    919   indexed_db_thread_.reset(new base::Thread("IndexedDB"));
    920   indexed_db_thread_->Start();
    921 #endif
    922 
    923 #if defined(OS_ANDROID)
    924   // Up the priority of anything that touches with display tasks
    925   // (this thread is UI thread, and io_thread_ is for IPCs).
    926   io_thread_->SetPriority(base::kThreadPriority_Display);
    927   base::PlatformThread::SetThreadPriority(
    928       base::PlatformThread::CurrentHandle(),
    929       base::kThreadPriority_Display);
    930 #endif
    931 
    932 #if !defined(OS_IOS)
    933   HistogramSynchronizer::GetInstance();
    934 
    935   bool initialize_gpu_data_manager = true;
    936 #if defined(OS_ANDROID)
    937   // On Android, GLSurface::InitializeOneOff() must be called before initalizing
    938   // the GpuDataManagerImpl as it uses the GL bindings. crbug.com/326295
    939   if (!gfx::GLSurface::InitializeOneOff()) {
    940     LOG(ERROR) << "GLSurface::InitializeOneOff failed";
    941     initialize_gpu_data_manager = false;
    942   }
    943 #endif
    944 
    945   // Initialize the GpuDataManager before we set up the MessageLoops because
    946   // otherwise we'll trigger the assertion about doing IO on the UI thread.
    947   if (initialize_gpu_data_manager)
    948     GpuDataManagerImpl::GetInstance()->Initialize();
    949 
    950   bool always_uses_gpu = true;
    951   bool established_gpu_channel = false;
    952 #if defined(USE_AURA) || defined(OS_MACOSX)
    953   if (ShouldInitializeBrowserGpuChannelAndTransportSurface()) {
    954     established_gpu_channel = true;
    955     if (!GpuDataManagerImpl::GetInstance()->CanUseGpuBrowserCompositor()) {
    956       established_gpu_channel = always_uses_gpu = false;
    957     }
    958     BrowserGpuChannelHostFactory::Initialize(established_gpu_channel);
    959     ImageTransportFactory::Initialize();
    960 #if defined(USE_AURA)
    961     if (aura::Env::GetInstance()) {
    962       aura::Env::GetInstance()->set_context_factory(
    963           content::GetContextFactory());
    964     }
    965 #endif
    966   }
    967 #elif defined(OS_ANDROID)
    968   established_gpu_channel = true;
    969   BrowserGpuChannelHostFactory::Initialize(established_gpu_channel);
    970 #endif
    971 
    972 #if defined(OS_LINUX) && defined(USE_UDEV)
    973   device_monitor_linux_.reset(new DeviceMonitorLinux());
    974 #elif defined(OS_MACOSX)
    975   device_monitor_mac_.reset(new DeviceMonitorMac());
    976 #endif
    977 
    978   // RDH needs the IO thread to be created
    979   {
    980     TRACE_EVENT0("startup",
    981       "BrowserMainLoop::BrowserThreadsStarted:InitResourceDispatcherHost");
    982     resource_dispatcher_host_.reset(new ResourceDispatcherHostImpl());
    983   }
    984 
    985   // MediaStreamManager needs the IO thread to be created.
    986   {
    987     TRACE_EVENT0("startup",
    988       "BrowserMainLoop::BrowserThreadsStarted:InitMediaStreamManager");
    989     media_stream_manager_.reset(new MediaStreamManager(audio_manager_.get()));
    990   }
    991 
    992   {
    993     TRACE_EVENT0("startup",
    994       "BrowserMainLoop::BrowserThreadsStarted:InitSpeechRecognition");
    995     speech_recognition_manager_.reset(new SpeechRecognitionManagerImpl(
    996         audio_manager_.get(), media_stream_manager_.get()));
    997   }
    998 
    999   {
   1000     TRACE_EVENT0(
   1001         "startup",
   1002         "BrowserMainLoop::BrowserThreadsStarted::InitUserInputMonitor");
   1003     user_input_monitor_ = media::UserInputMonitor::Create(
   1004         io_thread_->message_loop_proxy(), main_thread_->message_loop_proxy());
   1005   }
   1006 
   1007   {
   1008     TRACE_EVENT0("startup",
   1009                  "BrowserMainLoop::BrowserThreadsStarted::TimeZoneMonitor");
   1010     time_zone_monitor_ = TimeZoneMonitor::Create();
   1011   }
   1012 
   1013   // Alert the clipboard class to which threads are allowed to access the
   1014   // clipboard:
   1015   std::vector<base::PlatformThreadId> allowed_clipboard_threads;
   1016   // The current thread is the UI thread.
   1017   allowed_clipboard_threads.push_back(base::PlatformThread::CurrentId());
   1018 #if defined(OS_WIN)
   1019   // On Windows, clipboards are also used on the File or IO threads.
   1020   allowed_clipboard_threads.push_back(file_thread_->thread_id());
   1021   allowed_clipboard_threads.push_back(io_thread_->thread_id());
   1022 #endif
   1023   ui::Clipboard::SetAllowedThreads(allowed_clipboard_threads);
   1024 
   1025   // When running the GPU thread in-process, avoid optimistically starting it
   1026   // since creating the GPU thread races against creation of the one-and-only
   1027   // ChildProcess instance which is created by the renderer thread.
   1028   if (GpuDataManagerImpl::GetInstance()->GpuAccessAllowed(NULL) &&
   1029       !established_gpu_channel &&
   1030       always_uses_gpu &&
   1031       !parsed_command_line_.HasSwitch(switches::kSingleProcess) &&
   1032       !parsed_command_line_.HasSwitch(switches::kInProcessGPU)) {
   1033     TRACE_EVENT_INSTANT0("gpu", "Post task to launch GPU process",
   1034                          TRACE_EVENT_SCOPE_THREAD);
   1035     BrowserThread::PostTask(
   1036         BrowserThread::IO, FROM_HERE, base::Bind(
   1037             base::IgnoreResult(&GpuProcessHost::Get),
   1038             GpuProcessHost::GPU_PROCESS_KIND_SANDBOXED,
   1039             CAUSE_FOR_GPU_LAUNCH_BROWSER_STARTUP));
   1040   }
   1041 
   1042 #if defined(OS_MACOSX)
   1043   ThemeHelperMac::GetInstance();
   1044   if (ShouldEnableBootstrapSandbox()) {
   1045     TRACE_EVENT0("startup",
   1046         "BrowserMainLoop::BrowserThreadsStarted:BootstrapSandbox");
   1047     CHECK(GetBootstrapSandbox());
   1048   }
   1049 #endif  // defined(OS_MACOSX)
   1050 
   1051 #endif  // !defined(OS_IOS)
   1052 
   1053   return result_code_;
   1054 }
   1055 
   1056 bool BrowserMainLoop::InitializeToolkit() {
   1057   TRACE_EVENT0("startup", "BrowserMainLoop::InitializeToolkit");
   1058   // TODO(evan): this function is rather subtle, due to the variety
   1059   // of intersecting ifdefs we have.  To keep it easy to follow, there
   1060   // are no #else branches on any #ifs.
   1061   // TODO(stevenjb): Move platform specific code into platform specific Parts
   1062   // (Need to add InitializeToolkit stage to BrowserParts).
   1063   // See also GTK setup in EarlyInitialization, above, and associated comments.
   1064 
   1065 #if defined(OS_WIN)
   1066   // Init common control sex.
   1067   INITCOMMONCONTROLSEX config;
   1068   config.dwSize = sizeof(config);
   1069   config.dwICC = ICC_WIN95_CLASSES;
   1070   if (!InitCommonControlsEx(&config))
   1071     PLOG(FATAL);
   1072 #endif
   1073 
   1074 #if defined(USE_AURA)
   1075 
   1076 #if defined(USE_X11)
   1077   if (!gfx::GetXDisplay())
   1078     return false;
   1079 #endif
   1080 
   1081   // Env creates the compositor. Aura widgets need the compositor to be created
   1082   // before they can be initialized by the browser.
   1083   aura::Env::CreateInstance(true);
   1084 #endif  // defined(USE_AURA)
   1085 
   1086   if (parts_)
   1087     parts_->ToolkitInitialized();
   1088 
   1089   return true;
   1090 }
   1091 
   1092 void BrowserMainLoop::MainMessageLoopRun() {
   1093 #if defined(OS_ANDROID)
   1094   // Android's main message loop is the Java message loop.
   1095   NOTREACHED();
   1096 #else
   1097   DCHECK(base::MessageLoopForUI::IsCurrent());
   1098   if (parameters_.ui_task)
   1099     base::MessageLoopForUI::current()->PostTask(FROM_HERE,
   1100                                                 *parameters_.ui_task);
   1101 
   1102   base::RunLoop run_loop;
   1103   run_loop.Run();
   1104 #endif
   1105 }
   1106 
   1107 void BrowserMainLoop::InitStartupTracing(const CommandLine& command_line) {
   1108   DCHECK(is_tracing_startup_);
   1109 
   1110   base::FilePath trace_file = command_line.GetSwitchValuePath(
   1111       switches::kTraceStartupFile);
   1112   // trace_file = "none" means that startup events will show up for the next
   1113   // begin/end tracing (via about:tracing or AutomationProxy::BeginTracing/
   1114   // EndTracing, for example).
   1115   if (trace_file == base::FilePath().AppendASCII("none"))
   1116     return;
   1117 
   1118   if (trace_file.empty()) {
   1119 #if defined(OS_ANDROID)
   1120     TracingControllerAndroid::GenerateTracingFilePath(&trace_file);
   1121 #else
   1122     // Default to saving the startup trace into the current dir.
   1123     trace_file = base::FilePath().AppendASCII("chrometrace.log");
   1124 #endif
   1125   }
   1126 
   1127   std::string delay_str = command_line.GetSwitchValueASCII(
   1128       switches::kTraceStartupDuration);
   1129   int delay_secs = 5;
   1130   if (!delay_str.empty() && !base::StringToInt(delay_str, &delay_secs)) {
   1131     DLOG(WARNING) << "Could not parse --" << switches::kTraceStartupDuration
   1132         << "=" << delay_str << " defaulting to 5 (secs)";
   1133     delay_secs = 5;
   1134   }
   1135 
   1136   BrowserThread::PostDelayedTask(
   1137       BrowserThread::UI, FROM_HERE,
   1138       base::Bind(&BrowserMainLoop::EndStartupTracing,
   1139                  base::Unretained(this), trace_file),
   1140       base::TimeDelta::FromSeconds(delay_secs));
   1141 }
   1142 
   1143 void BrowserMainLoop::EndStartupTracing(const base::FilePath& trace_file) {
   1144   is_tracing_startup_ = false;
   1145   TracingController::GetInstance()->DisableRecording(
   1146       trace_file, base::Bind(&OnStoppedStartupTracing));
   1147 }
   1148 
   1149 }  // namespace content
   1150