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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 "chrome/browser/autocomplete/autocomplete_controller.h"
      6 
      7 #include <set>
      8 #include <string>
      9 
     10 #include "base/command_line.h"
     11 #include "base/format_macros.h"
     12 #include "base/logging.h"
     13 #include "base/metrics/histogram.h"
     14 #include "base/strings/string_number_conversions.h"
     15 #include "base/strings/stringprintf.h"
     16 #include "base/time/time.h"
     17 #include "chrome/browser/autocomplete/autocomplete_controller_delegate.h"
     18 #include "chrome/browser/autocomplete/bookmark_provider.h"
     19 #include "chrome/browser/autocomplete/builtin_provider.h"
     20 #include "chrome/browser/autocomplete/extension_app_provider.h"
     21 #include "chrome/browser/autocomplete/history_quick_provider.h"
     22 #include "chrome/browser/autocomplete/history_url_provider.h"
     23 #include "chrome/browser/autocomplete/keyword_provider.h"
     24 #include "chrome/browser/autocomplete/search_provider.h"
     25 #include "chrome/browser/autocomplete/shortcuts_provider.h"
     26 #include "chrome/browser/autocomplete/zero_suggest_provider.h"
     27 #include "chrome/browser/chrome_notification_types.h"
     28 #include "chrome/browser/omnibox/omnibox_field_trial.h"
     29 #include "chrome/browser/profiles/profile.h"
     30 #include "chrome/browser/search/search.h"
     31 #include "chrome/browser/search_engines/template_url.h"
     32 #include "chrome/common/chrome_switches.h"
     33 #include "content/public/browser/notification_service.h"
     34 #include "grit/generated_resources.h"
     35 #include "grit/theme_resources.h"
     36 #include "ui/base/l10n/l10n_util.h"
     37 
     38 #if defined(OS_CHROMEOS)
     39 #include "chrome/browser/autocomplete/contact_provider_chromeos.h"
     40 #include "chrome/browser/chromeos/contacts/contact_manager.h"
     41 #endif
     42 
     43 namespace {
     44 
     45 // Converts the given match to a type (and possibly subtype) based on the AQS
     46 // specification. For more details, see
     47 // http://goto.google.com/binary-clients-logging.
     48 void AutocompleteMatchToAssistedQuery(
     49     const AutocompleteMatch::Type& match, size_t* type, size_t* subtype) {
     50   // This type indicates a native chrome suggestion.
     51   *type = 69;
     52   // Default value, indicating no subtype.
     53   *subtype = string16::npos;
     54 
     55   switch (match) {
     56     case AutocompleteMatchType::SEARCH_SUGGEST: {
     57       *type = 0;
     58       return;
     59     }
     60     case AutocompleteMatchType::NAVSUGGEST: {
     61       *type = 5;
     62       return;
     63     }
     64     case AutocompleteMatchType::SEARCH_WHAT_YOU_TYPED: {
     65       *subtype = 57;
     66       return;
     67     }
     68     case AutocompleteMatchType::URL_WHAT_YOU_TYPED: {
     69       *subtype = 58;
     70       return;
     71     }
     72     case AutocompleteMatchType::SEARCH_HISTORY: {
     73       *subtype = 59;
     74       return;
     75     }
     76     case AutocompleteMatchType::HISTORY_URL: {
     77       *subtype = 60;
     78       return;
     79     }
     80     case AutocompleteMatchType::HISTORY_TITLE: {
     81       *subtype = 61;
     82       return;
     83     }
     84     case AutocompleteMatchType::HISTORY_BODY: {
     85       *subtype = 62;
     86       return;
     87     }
     88     case AutocompleteMatchType::HISTORY_KEYWORD: {
     89       *subtype = 63;
     90       return;
     91     }
     92     case AutocompleteMatchType::BOOKMARK_TITLE: {
     93       *subtype = 65;
     94       return;
     95     }
     96     default: {
     97       // This value indicates a native chrome suggestion with no named subtype
     98       // (yet).
     99       *subtype = 64;
    100     }
    101   }
    102 }
    103 
    104 // Appends available autocompletion of the given type, subtype, and number to
    105 // the existing available autocompletions string, encoding according to the
    106 // spec.
    107 void AppendAvailableAutocompletion(size_t type,
    108                                    size_t subtype,
    109                                    int count,
    110                                    std::string* autocompletions) {
    111   if (!autocompletions->empty())
    112     autocompletions->append("j");
    113   base::StringAppendF(autocompletions, "%" PRIuS, type);
    114   // Subtype is optional - string16::npos indicates no subtype.
    115   if (subtype != string16::npos)
    116     base::StringAppendF(autocompletions, "i%" PRIuS, subtype);
    117   if (count > 1)
    118     base::StringAppendF(autocompletions, "l%d", count);
    119 }
    120 
    121 // Returns whether the autocompletion is trivial enough that we consider it
    122 // an autocompletion for which the omnibox autocompletion code did not add
    123 // any value.
    124 bool IsTrivialAutocompletion(const AutocompleteMatch& match) {
    125   return match.type == AutocompleteMatchType::SEARCH_WHAT_YOU_TYPED ||
    126       match.type == AutocompleteMatchType::URL_WHAT_YOU_TYPED ||
    127       match.type == AutocompleteMatchType::SEARCH_OTHER_ENGINE;
    128 }
    129 
    130 }  // namespace
    131 
    132 const int AutocompleteController::kNoItemSelected = -1;
    133 
    134 AutocompleteController::AutocompleteController(
    135     Profile* profile,
    136     AutocompleteControllerDelegate* delegate,
    137     int provider_types)
    138     : delegate_(delegate),
    139       history_url_provider_(NULL),
    140       keyword_provider_(NULL),
    141       search_provider_(NULL),
    142       zero_suggest_provider_(NULL),
    143       in_stop_timer_field_trial_(
    144           OmniboxFieldTrial::InStopTimerFieldTrialExperimentGroup()),
    145       done_(true),
    146       in_start_(false),
    147       in_zero_suggest_(false),
    148       profile_(profile) {
    149   // AND with the disabled providers, if any.
    150   provider_types &= ~OmniboxFieldTrial::GetDisabledProviderTypes();
    151   bool use_hqp = !!(provider_types & AutocompleteProvider::TYPE_HISTORY_QUICK);
    152   // TODO(mrossetti): Permanently modify the HistoryURLProvider to not search
    153   // titles once HQP is turned on permanently.
    154 
    155   if (provider_types & AutocompleteProvider::TYPE_BUILTIN)
    156     providers_.push_back(new BuiltinProvider(this, profile));
    157 #if defined(OS_CHROMEOS)
    158   if (provider_types & AutocompleteProvider::TYPE_CONTACT)
    159     providers_.push_back(new ContactProvider(this, profile,
    160         contacts::ContactManager::GetInstance()->GetWeakPtr()));
    161 #endif
    162   if (provider_types & AutocompleteProvider::TYPE_EXTENSION_APP)
    163     providers_.push_back(new ExtensionAppProvider(this, profile));
    164   if (use_hqp)
    165     providers_.push_back(new HistoryQuickProvider(this, profile));
    166   if (provider_types & AutocompleteProvider::TYPE_HISTORY_URL) {
    167     history_url_provider_ = new HistoryURLProvider(this, profile);
    168     providers_.push_back(history_url_provider_);
    169   }
    170   // Search provider/"tab to search" can be used on all platforms other than
    171   // Android.
    172 #if !defined(OS_ANDROID)
    173   if (provider_types & AutocompleteProvider::TYPE_KEYWORD) {
    174     keyword_provider_ = new KeywordProvider(this, profile);
    175     providers_.push_back(keyword_provider_);
    176   }
    177 #endif
    178   if (provider_types & AutocompleteProvider::TYPE_SEARCH) {
    179     search_provider_ = new SearchProvider(this, profile);
    180     providers_.push_back(search_provider_);
    181   }
    182   if (provider_types & AutocompleteProvider::TYPE_SHORTCUTS)
    183     providers_.push_back(new ShortcutsProvider(this, profile));
    184 
    185   // Create ZeroSuggest if it is enabled.
    186   if (provider_types & AutocompleteProvider::TYPE_ZERO_SUGGEST) {
    187     zero_suggest_provider_ = ZeroSuggestProvider::Create(this, profile);
    188     if (zero_suggest_provider_)
    189       providers_.push_back(zero_suggest_provider_);
    190   }
    191 
    192   if ((provider_types & AutocompleteProvider::TYPE_BOOKMARK) &&
    193       !CommandLine::ForCurrentProcess()->HasSwitch(
    194           switches::kDisableBookmarkAutocompleteProvider))
    195     providers_.push_back(new BookmarkProvider(this, profile));
    196 
    197   for (ACProviders::iterator i(providers_.begin()); i != providers_.end(); ++i)
    198     (*i)->AddRef();
    199 }
    200 
    201 AutocompleteController::~AutocompleteController() {
    202   // The providers may have tasks outstanding that hold refs to them.  We need
    203   // to ensure they won't call us back if they outlive us.  (Practically,
    204   // calling Stop() should also cancel those tasks and make it so that we hold
    205   // the only refs.)  We also don't want to bother notifying anyone of our
    206   // result changes here, because the notification observer is in the midst of
    207   // shutdown too, so we don't ask Stop() to clear |result_| (and notify).
    208   result_.Reset();  // Not really necessary.
    209   Stop(false);
    210 
    211   for (ACProviders::iterator i(providers_.begin()); i != providers_.end(); ++i)
    212     (*i)->Release();
    213 
    214   providers_.clear();  // Not really necessary.
    215 }
    216 
    217 void AutocompleteController::Start(const AutocompleteInput& input) {
    218   const string16 old_input_text(input_.text());
    219   const AutocompleteInput::MatchesRequested old_matches_requested =
    220       input_.matches_requested();
    221   input_ = input;
    222 
    223   // See if we can avoid rerunning autocomplete when the query hasn't changed
    224   // much.  When the user presses or releases the ctrl key, the desired_tld
    225   // changes, and when the user finishes an IME composition, inline autocomplete
    226   // may no longer be prevented.  In both these cases the text itself hasn't
    227   // changed since the last query, and some providers can do much less work (and
    228   // get matches back more quickly).  Taking advantage of this reduces flicker.
    229   //
    230   // NOTE: This comes after constructing |input_| above since that construction
    231   // can change the text string (e.g. by stripping off a leading '?').
    232   const bool minimal_changes = (input_.text() == old_input_text) &&
    233       (input_.matches_requested() == old_matches_requested);
    234 
    235   expire_timer_.Stop();
    236   stop_timer_.Stop();
    237 
    238   // Start the new query.
    239   in_zero_suggest_ = false;
    240   in_start_ = true;
    241   base::TimeTicks start_time = base::TimeTicks::Now();
    242   for (ACProviders::iterator i(providers_.begin()); i != providers_.end();
    243        ++i) {
    244     // TODO(mpearson): Remove timing code once bugs 178705 / 237703 / 168933
    245     // are resolved.
    246     base::TimeTicks provider_start_time = base::TimeTicks::Now();
    247     (*i)->Start(input_, minimal_changes);
    248     if (input.matches_requested() != AutocompleteInput::ALL_MATCHES)
    249       DCHECK((*i)->done());
    250     base::TimeTicks provider_end_time = base::TimeTicks::Now();
    251     std::string name = std::string("Omnibox.ProviderTime.") + (*i)->GetName();
    252     base::HistogramBase* counter = base::Histogram::FactoryGet(
    253         name, 1, 5000, 20, base::Histogram::kUmaTargetedHistogramFlag);
    254     counter->Add(static_cast<int>(
    255         (provider_end_time - provider_start_time).InMilliseconds()));
    256   }
    257   if (input.matches_requested() == AutocompleteInput::ALL_MATCHES &&
    258       (input.text().length() < 6)) {
    259     base::TimeTicks end_time = base::TimeTicks::Now();
    260     std::string name = "Omnibox.QueryTime." + base::IntToString(
    261         input.text().length());
    262     base::HistogramBase* counter = base::Histogram::FactoryGet(
    263         name, 1, 1000, 50, base::Histogram::kUmaTargetedHistogramFlag);
    264     counter->Add(static_cast<int>((end_time - start_time).InMilliseconds()));
    265   }
    266   in_start_ = false;
    267   CheckIfDone();
    268   // The second true forces saying the default match has changed.
    269   // This triggers the edit model to update things such as the inline
    270   // autocomplete state.  In particular, if the user has typed a key
    271   // since the last notification, and we're now re-running
    272   // autocomplete, then we need to update the inline autocompletion
    273   // even if the current match is for the same URL as the last run's
    274   // default match.  Likewise, the controller doesn't know what's
    275   // happened in the edit since the last time it ran autocomplete.
    276   // The user might have selected all the text and hit delete, then
    277   // typed a new character.  The selection and delete won't send any
    278   // signals to the controller so it doesn't realize that anything was
    279   // cleared or changed.  Even if the default match hasn't changed, we
    280   // need the edit model to update the display.
    281   UpdateResult(false, true);
    282 
    283   if (!done_) {
    284     StartExpireTimer();
    285     StartStopTimer();
    286   }
    287 }
    288 
    289 void AutocompleteController::Stop(bool clear_result) {
    290   for (ACProviders::const_iterator i(providers_.begin()); i != providers_.end();
    291        ++i) {
    292     (*i)->Stop(clear_result);
    293   }
    294 
    295   expire_timer_.Stop();
    296   stop_timer_.Stop();
    297   done_ = true;
    298   if (clear_result && !result_.empty()) {
    299     result_.Reset();
    300     // NOTE: We pass in false since we're trying to only clear the popup, not
    301     // touch the edit... this is all a mess and should be cleaned up :(
    302     NotifyChanged(false);
    303   }
    304 }
    305 
    306 void AutocompleteController::StartZeroSuggest(
    307     const GURL& url,
    308     AutocompleteInput::PageClassification page_classification,
    309     const string16& permanent_text) {
    310   if (zero_suggest_provider_ != NULL) {
    311     DCHECK(!in_start_);  // We should not be already running a query.
    312     in_zero_suggest_ = true;
    313     zero_suggest_provider_->StartZeroSuggest(
    314         url, page_classification, permanent_text);
    315   }
    316 }
    317 
    318 void AutocompleteController::StopZeroSuggest() {
    319   if (zero_suggest_provider_ != NULL) {
    320     DCHECK(!in_start_);  // We should not be already running a query.
    321     zero_suggest_provider_->Stop(false);
    322   }
    323 }
    324 
    325 void AutocompleteController::DeleteMatch(const AutocompleteMatch& match) {
    326   DCHECK(match.deletable);
    327   match.provider->DeleteMatch(match);  // This may synchronously call back to
    328                                        // OnProviderUpdate().
    329   // If DeleteMatch resulted in a callback to OnProviderUpdate and we're
    330   // not done, we might attempt to redisplay the deleted match. Make sure
    331   // we aren't displaying it by removing any old entries.
    332   ExpireCopiedEntries();
    333 }
    334 
    335 void AutocompleteController::ExpireCopiedEntries() {
    336   // The first true makes UpdateResult() clear out the results and
    337   // regenerate them, thus ensuring that no results from the previous
    338   // result set remain.
    339   UpdateResult(true, false);
    340 }
    341 
    342 void AutocompleteController::OnProviderUpdate(bool updated_matches) {
    343   if (in_zero_suggest_) {
    344     // We got ZeroSuggest results before Start(). Show only those results,
    345     // because results from other providers are stale.
    346     result_.Reset();
    347     result_.AppendMatches(zero_suggest_provider_->matches());
    348     result_.SortAndCull(input_, profile_);
    349     UpdateAssistedQueryStats(&result_);
    350     NotifyChanged(true);
    351   } else {
    352     CheckIfDone();
    353     // Multiple providers may provide synchronous results, so we only update the
    354     // results if we're not in Start().
    355     if (!in_start_ && (updated_matches || done_))
    356       UpdateResult(false, false);
    357   }
    358 }
    359 
    360 void AutocompleteController::AddProvidersInfo(
    361     ProvidersInfo* provider_info) const {
    362   provider_info->clear();
    363   for (ACProviders::const_iterator i(providers_.begin()); i != providers_.end();
    364        ++i) {
    365     // Add per-provider info, if any.
    366     (*i)->AddProviderInfo(provider_info);
    367 
    368     // This is also a good place to put code to add info that you want to
    369     // add for every provider.
    370   }
    371 }
    372 
    373 void AutocompleteController::ResetSession() {
    374   for (ACProviders::const_iterator i(providers_.begin()); i != providers_.end();
    375        ++i)
    376     (*i)->ResetSession();
    377   in_zero_suggest_ = false;
    378 }
    379 
    380 void AutocompleteController::UpdateResult(
    381     bool regenerate_result,
    382     bool force_notify_default_match_changed) {
    383   const bool last_default_was_valid = result_.default_match() != result_.end();
    384   // The following three variables are only set and used if
    385   // |last_default_was_valid|.
    386   string16 last_default_fill_into_edit, last_default_keyword,
    387       last_default_associated_keyword;
    388   if (last_default_was_valid) {
    389     last_default_fill_into_edit = result_.default_match()->fill_into_edit;
    390     last_default_keyword = result_.default_match()->keyword;
    391     if (result_.default_match()->associated_keyword != NULL)
    392       last_default_associated_keyword =
    393           result_.default_match()->associated_keyword->keyword;
    394   }
    395 
    396   if (regenerate_result)
    397     result_.Reset();
    398 
    399   AutocompleteResult last_result;
    400   last_result.Swap(&result_);
    401 
    402   for (ACProviders::const_iterator i(providers_.begin()); i != providers_.end();
    403        ++i)
    404     result_.AppendMatches((*i)->matches());
    405 
    406   // Sort the matches and trim to a small number of "best" matches.
    407   result_.SortAndCull(input_, profile_);
    408 
    409   // Need to validate before invoking CopyOldMatches as the old matches are not
    410   // valid against the current input.
    411 #ifndef NDEBUG
    412   result_.Validate();
    413 #endif
    414 
    415   if (!done_) {
    416     // This conditional needs to match the conditional in Start that invokes
    417     // StartExpireTimer.
    418     result_.CopyOldMatches(input_, last_result, profile_);
    419   }
    420 
    421   UpdateKeywordDescriptions(&result_);
    422   UpdateAssociatedKeywords(&result_);
    423   UpdateAssistedQueryStats(&result_);
    424 
    425   const bool default_is_valid = result_.default_match() != result_.end();
    426   string16 default_associated_keyword;
    427   if (default_is_valid &&
    428       (result_.default_match()->associated_keyword != NULL)) {
    429     default_associated_keyword =
    430         result_.default_match()->associated_keyword->keyword;
    431   }
    432   // We've gotten async results. Send notification that the default match
    433   // updated if fill_into_edit, associated_keyword, or keyword differ.  (The
    434   // second can change if we've just started Chrome and the keyword database
    435   // finishes loading while processing this request.  The third can change
    436   // if we swapped from interpreting the input as a search--which gets
    437   // labeled with the default search provider's keyword--to a URL.)
    438   // We don't check the URL as that may change for the default match
    439   // even though the fill into edit hasn't changed (see SearchProvider
    440   // for one case of this).
    441   const bool notify_default_match =
    442       (last_default_was_valid != default_is_valid) ||
    443       (last_default_was_valid &&
    444        ((result_.default_match()->fill_into_edit !=
    445           last_default_fill_into_edit) ||
    446         (default_associated_keyword != last_default_associated_keyword) ||
    447         (result_.default_match()->keyword != last_default_keyword)));
    448   if (notify_default_match)
    449     last_time_default_match_changed_ = base::TimeTicks::Now();
    450 
    451   NotifyChanged(force_notify_default_match_changed || notify_default_match);
    452 }
    453 
    454 void AutocompleteController::UpdateAssociatedKeywords(
    455     AutocompleteResult* result) {
    456   if (!keyword_provider_)
    457     return;
    458 
    459   std::set<string16> keywords;
    460   for (ACMatches::iterator match(result->begin()); match != result->end();
    461        ++match) {
    462     string16 keyword(match->GetSubstitutingExplicitlyInvokedKeyword(profile_));
    463     if (!keyword.empty()) {
    464       keywords.insert(keyword);
    465       continue;
    466     }
    467 
    468     // Only add the keyword if the match does not have a duplicate keyword with
    469     // a more relevant match.
    470     keyword = match->associated_keyword.get() ?
    471         match->associated_keyword->keyword :
    472         keyword_provider_->GetKeywordForText(match->fill_into_edit);
    473     if (!keyword.empty() && !keywords.count(keyword)) {
    474       keywords.insert(keyword);
    475 
    476       if (!match->associated_keyword.get())
    477         match->associated_keyword.reset(new AutocompleteMatch(
    478             keyword_provider_->CreateVerbatimMatch(match->fill_into_edit,
    479                                                    keyword, input_)));
    480     } else {
    481       match->associated_keyword.reset();
    482     }
    483   }
    484 }
    485 
    486 void AutocompleteController::UpdateAssistedQueryStats(
    487     AutocompleteResult* result) {
    488   if (result->empty())
    489     return;
    490 
    491   // Build the impressions string (the AQS part after ".").
    492   std::string autocompletions;
    493   int count = 0;
    494   size_t last_type = string16::npos;
    495   size_t last_subtype = string16::npos;
    496   for (ACMatches::iterator match(result->begin()); match != result->end();
    497        ++match) {
    498     size_t type = string16::npos;
    499     size_t subtype = string16::npos;
    500     AutocompleteMatchToAssistedQuery(match->type, &type, &subtype);
    501     if (last_type != string16::npos &&
    502         (type != last_type || subtype != last_subtype)) {
    503       AppendAvailableAutocompletion(
    504           last_type, last_subtype, count, &autocompletions);
    505       count = 1;
    506     } else {
    507       count++;
    508     }
    509     last_type = type;
    510     last_subtype = subtype;
    511   }
    512   AppendAvailableAutocompletion(
    513       last_type, last_subtype, count, &autocompletions);
    514   // Go over all matches and set AQS if the match supports it.
    515   for (size_t index = 0; index < result->size(); ++index) {
    516     AutocompleteMatch* match = result->match_at(index);
    517     const TemplateURL* template_url = match->GetTemplateURL(profile_, false);
    518     if (!template_url || !match->search_terms_args.get())
    519       continue;
    520     std::string selected_index;
    521     // Prevent trivial suggestions from getting credit for being selected.
    522     if (!IsTrivialAutocompletion(*match))
    523       selected_index = base::StringPrintf("%" PRIuS, index);
    524     match->search_terms_args->assisted_query_stats =
    525         base::StringPrintf("chrome.%s.%s",
    526                            selected_index.c_str(),
    527                            autocompletions.c_str());
    528     match->destination_url = GURL(template_url->url_ref().ReplaceSearchTerms(
    529         *match->search_terms_args));
    530   }
    531 }
    532 
    533 GURL AutocompleteController::GetDestinationURL(
    534     const AutocompleteMatch& match,
    535     base::TimeDelta query_formulation_time) const {
    536   GURL destination_url(match.destination_url);
    537   TemplateURL* template_url = match.GetTemplateURL(profile_, false);
    538 
    539   // Append the query formulation time (time from when the user first typed a
    540   // character into the omnibox to when the user selected a query) and whether
    541   // a field trial has triggered to the AQS parameter, if other AQS parameters
    542   // were already populated.
    543   if (template_url && match.search_terms_args.get() &&
    544       !match.search_terms_args->assisted_query_stats.empty()) {
    545     TemplateURLRef::SearchTermsArgs search_terms_args(*match.search_terms_args);
    546     search_terms_args.assisted_query_stats += base::StringPrintf(
    547         ".%" PRId64 "j%dj%d",
    548         query_formulation_time.InMilliseconds(),
    549         (search_provider_ &&
    550          search_provider_->field_trial_triggered_in_session()) ||
    551         (zero_suggest_provider_ &&
    552          zero_suggest_provider_->field_trial_triggered_in_session()),
    553         input_.current_page_classification());
    554     destination_url = GURL(template_url->url_ref().
    555                            ReplaceSearchTerms(search_terms_args));
    556   }
    557   return destination_url;
    558 }
    559 
    560 void AutocompleteController::UpdateKeywordDescriptions(
    561     AutocompleteResult* result) {
    562   string16 last_keyword;
    563   for (AutocompleteResult::iterator i(result->begin()); i != result->end();
    564        ++i) {
    565     if ((i->provider->type() == AutocompleteProvider::TYPE_KEYWORD &&
    566          !i->keyword.empty()) ||
    567         (i->provider->type() == AutocompleteProvider::TYPE_SEARCH &&
    568          AutocompleteMatch::IsSearchType(i->type))) {
    569       i->description.clear();
    570       i->description_class.clear();
    571       DCHECK(!i->keyword.empty());
    572       if (i->keyword != last_keyword) {
    573         const TemplateURL* template_url = i->GetTemplateURL(profile_, false);
    574         if (template_url) {
    575           // For extension keywords, just make the description the extension
    576           // name -- don't assume that the normal search keyword description is
    577           // applicable.
    578           i->description = template_url->AdjustedShortNameForLocaleDirection();
    579           if (!template_url->IsExtensionKeyword()) {
    580             i->description = l10n_util::GetStringFUTF16(
    581                 IDS_AUTOCOMPLETE_SEARCH_DESCRIPTION, i->description);
    582           }
    583           i->description_class.push_back(
    584               ACMatchClassification(0, ACMatchClassification::DIM));
    585         }
    586         last_keyword = i->keyword;
    587       }
    588     } else {
    589       last_keyword.clear();
    590     }
    591   }
    592 }
    593 
    594 void AutocompleteController::NotifyChanged(bool notify_default_match) {
    595   if (delegate_)
    596     delegate_->OnResultChanged(notify_default_match);
    597   if (done_) {
    598     content::NotificationService::current()->Notify(
    599         chrome::NOTIFICATION_AUTOCOMPLETE_CONTROLLER_RESULT_READY,
    600         content::Source<AutocompleteController>(this),
    601         content::NotificationService::NoDetails());
    602   }
    603 }
    604 
    605 void AutocompleteController::CheckIfDone() {
    606   for (ACProviders::const_iterator i(providers_.begin()); i != providers_.end();
    607        ++i) {
    608     if (!(*i)->done()) {
    609       done_ = false;
    610       return;
    611     }
    612   }
    613   done_ = true;
    614 }
    615 
    616 void AutocompleteController::StartExpireTimer() {
    617   // Amount of time (in ms) between when the user stops typing and
    618   // when we remove any copied entries. We do this from the time the
    619   // user stopped typing as some providers (such as SearchProvider)
    620   // wait for the user to stop typing before they initiate a query.
    621   const int kExpireTimeMS = 500;
    622 
    623   if (result_.HasCopiedMatches())
    624     expire_timer_.Start(FROM_HERE,
    625                         base::TimeDelta::FromMilliseconds(kExpireTimeMS),
    626                         this, &AutocompleteController::ExpireCopiedEntries);
    627 }
    628 
    629 void AutocompleteController::StartStopTimer() {
    630   if (!in_stop_timer_field_trial_)
    631     return;
    632 
    633   // Amount of time (in ms) between when the user stops typing and
    634   // when we send Stop() to every provider.  This is intended to avoid
    635   // the disruptive effect of belated omnibox updates, updates that
    636   // come after the user has had to time to read the whole dropdown
    637   // and doesn't expect it to change.
    638   const int kStopTimeMS = 1500;
    639   stop_timer_.Start(FROM_HERE,
    640                     base::TimeDelta::FromMilliseconds(kStopTimeMS),
    641                     base::Bind(&AutocompleteController::Stop,
    642                                base::Unretained(this),
    643                                false));
    644 }
    645