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      1 // Copyright 2013 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 "ash/wm/window_positioner.h"
      6 
      7 #include "ash/ash_switches.h"
      8 #include "ash/screen_util.h"
      9 #include "ash/shell.h"
     10 #include "ash/shell_window_ids.h"
     11 #include "ash/wm/mru_window_tracker.h"
     12 #include "ash/wm/window_resizer.h"
     13 #include "ash/wm/window_state.h"
     14 #include "ash/wm/window_util.h"
     15 #include "base/command_line.h"
     16 #include "ui/aura/window.h"
     17 #include "ui/aura/window_delegate.h"
     18 #include "ui/aura/window_event_dispatcher.h"
     19 #include "ui/compositor/layer.h"
     20 #include "ui/compositor/scoped_layer_animation_settings.h"
     21 #include "ui/gfx/screen.h"
     22 #include "ui/wm/core/window_animations.h"
     23 #include "ui/wm/core/window_util.h"
     24 
     25 namespace ash {
     26 
     27 const int WindowPositioner::kMinimumWindowOffset = 32;
     28 
     29 // The number of pixels which are kept free top, left and right when a window
     30 // gets positioned to its default location.
     31 // static
     32 const int WindowPositioner::kDesktopBorderSize = 16;
     33 
     34 // Maximum width of a window even if there is more room on the desktop.
     35 // static
     36 const int WindowPositioner::kMaximumWindowWidth = 1100;
     37 
     38 namespace {
     39 
     40 // When a window gets opened in default mode and the screen is less than or
     41 // equal to this width, the window will get opened in maximized mode. This value
     42 // can be reduced to a "tame" number if the feature is disabled.
     43 const int kForceMaximizeWidthLimit = 1366;
     44 
     45 // The time in milliseconds which should be used to visually move a window
     46 // through an automatic "intelligent" window management option.
     47 const int kWindowAutoMoveDurationMS = 125;
     48 
     49 // If set to true all window repositioning actions will be ignored. Set through
     50 // WindowPositioner::SetIgnoreActivations().
     51 static bool disable_auto_positioning = false;
     52 
     53 // If set to true, by default the first window in ASH will be maximized.
     54 static bool maximize_first_window = false;
     55 
     56 // Check if any management should be performed (with a given |window|).
     57 bool UseAutoWindowManager(const aura::Window* window) {
     58   if (disable_auto_positioning)
     59     return false;
     60   const wm::WindowState* window_state = wm::GetWindowState(window);
     61   return !window_state->is_dragged() && window_state->window_position_managed();
     62 }
     63 
     64 // Check if a given |window| can be managed. This includes that it's state is
     65 // not minimized/maximized/the user has changed it's size by hand already.
     66 // It furthermore checks for the WindowIsManaged status.
     67 bool WindowPositionCanBeManaged(const aura::Window* window) {
     68   if (disable_auto_positioning)
     69     return false;
     70   const wm::WindowState* window_state = wm::GetWindowState(window);
     71   return window_state->window_position_managed() &&
     72       !window_state->IsMinimized() &&
     73       !window_state->IsMaximized() &&
     74       !window_state->bounds_changed_by_user();
     75 }
     76 
     77 // Get the work area for a given |window| in parent coordinates.
     78 gfx::Rect GetWorkAreaForWindowInParent(aura::Window* window) {
     79 #if defined(OS_WIN)
     80   // On Win 8, the host window can't be resized, so
     81   // use window's bounds instead.
     82   // TODO(oshima): Emulate host window resize on win8.
     83   gfx::Rect work_area = gfx::Rect(window->parent()->bounds().size());
     84   work_area.Inset(Shell::GetScreen()->GetDisplayMatching(
     85       window->parent()->GetBoundsInScreen()).GetWorkAreaInsets());
     86   return work_area;
     87 #else
     88   return ScreenUtil::GetDisplayWorkAreaBoundsInParent(window);
     89 #endif
     90 }
     91 
     92 // Move the given |bounds| on the available |work_area| in the direction
     93 // indicated by |move_right|. If |move_right| is true, the rectangle gets moved
     94 // to the right edge, otherwise to the left one.
     95 bool MoveRectToOneSide(const gfx::Rect& work_area,
     96                        bool move_right,
     97                        gfx::Rect* bounds) {
     98   if (move_right) {
     99     if (work_area.right() > bounds->right()) {
    100       bounds->set_x(work_area.right() - bounds->width());
    101       return true;
    102     }
    103   } else {
    104     if (work_area.x() < bounds->x()) {
    105       bounds->set_x(work_area.x());
    106       return true;
    107     }
    108   }
    109   return false;
    110 }
    111 
    112 // Move a |window| to new |bounds|. Animate if desired by user.
    113 // Moves the transient children of the |window| as well by the same |offset| as
    114 // the parent |window|.
    115 void SetBoundsAndOffsetTransientChildren(aura::Window* window,
    116                                          const gfx::Rect& bounds,
    117                                          const gfx::Rect& work_area,
    118                                          const gfx::Vector2d& offset) {
    119   aura::Window::Windows transient_children =
    120       ::wm::GetTransientChildren(window);
    121   for (aura::Window::Windows::iterator iter = transient_children.begin();
    122       iter != transient_children.end(); ++iter) {
    123     aura::Window* transient_child = *iter;
    124     gfx::Rect child_bounds = transient_child->bounds();
    125     gfx::Rect new_child_bounds = child_bounds + offset;
    126     if ((child_bounds.x() <= work_area.x() &&
    127          new_child_bounds.x() <= work_area.x()) ||
    128         (child_bounds.right() >= work_area.right() &&
    129          new_child_bounds.right() >= work_area.right())) {
    130       continue;
    131     }
    132     if (new_child_bounds.right() > work_area.right())
    133       new_child_bounds.set_x(work_area.right() - bounds.width());
    134     else if (new_child_bounds.x() < work_area.x())
    135       new_child_bounds.set_x(work_area.x());
    136     SetBoundsAndOffsetTransientChildren(transient_child,
    137                                         new_child_bounds, work_area, offset);
    138   }
    139 
    140   if (::wm::WindowAnimationsDisabled(window)) {
    141     window->SetBounds(bounds);
    142     return;
    143   }
    144 
    145   ui::ScopedLayerAnimationSettings settings(window->layer()->GetAnimator());
    146   settings.SetTransitionDuration(
    147       base::TimeDelta::FromMilliseconds(kWindowAutoMoveDurationMS));
    148   window->SetBounds(bounds);
    149 }
    150 
    151 // Move a |window| to new |bounds|. Animate if desired by user.
    152 // Note: The function will do nothing if the bounds did not change.
    153 void SetBoundsAnimated(aura::Window* window,
    154                        const gfx::Rect& bounds,
    155                        const gfx::Rect& work_area) {
    156   gfx::Rect old_bounds = window->GetTargetBounds();
    157   if (bounds == old_bounds)
    158     return;
    159   gfx::Vector2d offset(bounds.origin() - old_bounds.origin());
    160   SetBoundsAndOffsetTransientChildren(window, bounds, work_area, offset);
    161 }
    162 
    163 // Move |window| into the center of the screen - or restore it to the previous
    164 // position.
    165 void AutoPlaceSingleWindow(aura::Window* window, bool animated) {
    166   gfx::Rect work_area = GetWorkAreaForWindowInParent(window);
    167   gfx::Rect bounds = window->bounds();
    168   const gfx::Rect* user_defined_area =
    169       wm::GetWindowState(window)->pre_auto_manage_window_bounds();
    170   if (user_defined_area) {
    171     bounds = *user_defined_area;
    172     ash::wm::AdjustBoundsToEnsureMinimumWindowVisibility(work_area, &bounds);
    173   } else {
    174     // Center the window (only in x).
    175     bounds.set_x(work_area.x() + (work_area.width() - bounds.width()) / 2);
    176   }
    177 
    178   if (animated)
    179     SetBoundsAnimated(window, bounds, work_area);
    180   else
    181     window->SetBounds(bounds);
    182 }
    183 
    184 // Get the first open (non minimized) window which is on the screen defined.
    185 aura::Window* GetReferenceWindow(const aura::Window* root_window,
    186                                  const aura::Window* exclude,
    187                                  bool *single_window) {
    188   if (single_window)
    189     *single_window = true;
    190   // Get the active window.
    191   aura::Window* active = ash::wm::GetActiveWindow();
    192   if (active && active->GetRootWindow() != root_window)
    193     active = NULL;
    194 
    195   // Get a list of all windows.
    196   const std::vector<aura::Window*> windows =
    197       ash::MruWindowTracker::BuildWindowList(false);
    198 
    199   if (windows.empty())
    200     return NULL;
    201 
    202   aura::Window::Windows::const_iterator iter = windows.begin();
    203   // Find the index of the current active window.
    204   if (active)
    205     iter = std::find(windows.begin(), windows.end(), active);
    206 
    207   int index = (iter == windows.end()) ? 0 : (iter - windows.begin());
    208 
    209   // Scan the cycle list backwards to see which is the second topmost window
    210   // (and so on). Note that we might cycle a few indices twice if there is no
    211   // suitable window. However - since the list is fairly small this should be
    212   // very fast anyways.
    213   aura::Window* found = NULL;
    214   for (int i = index + windows.size(); i >= 0; i--) {
    215     aura::Window* window = windows[i % windows.size()];
    216     while (::wm::GetTransientParent(window))
    217       window = ::wm::GetTransientParent(window);
    218     if (window != exclude && window->type() == ui::wm::WINDOW_TYPE_NORMAL &&
    219         window->GetRootWindow() == root_window && window->TargetVisibility() &&
    220         wm::GetWindowState(window)->window_position_managed()) {
    221       if (found && found != window) {
    222         // no need to check !single_window because the function must have
    223         // been already returned in the "if (!single_window)" below.
    224         *single_window = false;
    225         return found;
    226       }
    227       found = window;
    228       // If there is no need to check single window, return now.
    229       if (!single_window)
    230         return found;
    231     }
    232   }
    233   return found;
    234 }
    235 
    236 }  // namespace
    237 
    238 // static
    239 int WindowPositioner::GetForceMaximizedWidthLimit() {
    240   return kForceMaximizeWidthLimit;
    241 }
    242 
    243 // static
    244 void WindowPositioner::GetBoundsAndShowStateForNewWindow(
    245     const gfx::Screen* screen,
    246     const aura::Window* new_window,
    247     bool is_saved_bounds,
    248     ui::WindowShowState show_state_in,
    249     gfx::Rect* bounds_in_out,
    250     ui::WindowShowState* show_state_out) {
    251 
    252   // Always open new window in the target display.
    253   aura::Window* target = Shell::GetTargetRootWindow();
    254 
    255   aura::Window* top_window = GetReferenceWindow(target, NULL, NULL);
    256   // Our window should not have any impact if we are already on top.
    257   if (top_window == new_window)
    258     top_window = NULL;
    259 
    260   // If there is no valid other window we take and adjust the passed coordinates
    261   // and show state.
    262   if (!top_window) {
    263     gfx::Rect work_area = screen->GetDisplayNearestWindow(target).work_area();
    264 
    265     bounds_in_out->AdjustToFit(work_area);
    266     // Use adjusted saved bounds, if there is one.
    267     if (is_saved_bounds)
    268       return;
    269     // When using "small screens" we want to always open in full screen mode.
    270     if (show_state_in == ui::SHOW_STATE_DEFAULT && (maximize_first_window ||
    271          (work_area.width() <= GetForceMaximizedWidthLimit() &&
    272          (!new_window || !wm::GetWindowState(new_window)->IsFullscreen())))) {
    273       *show_state_out = ui::SHOW_STATE_MAXIMIZED;
    274     }
    275     return;
    276   }
    277   wm::WindowState* top_window_state = wm::GetWindowState(top_window);
    278   bool maximized = top_window_state->IsMaximized();
    279   // We ignore the saved show state, but look instead for the top level
    280   // window's show state.
    281   if (show_state_in == ui::SHOW_STATE_DEFAULT) {
    282     *show_state_out = maximized ? ui::SHOW_STATE_MAXIMIZED :
    283         ui::SHOW_STATE_DEFAULT;
    284   }
    285 
    286   if (maximized) {
    287     bool has_restore_bounds = top_window_state->HasRestoreBounds();
    288     if (has_restore_bounds) {
    289       // For a maximized window ignore the real bounds of the top level window
    290       // and use its restore bounds instead. Offset the bounds to prevent the
    291       // windows from overlapping exactly when restored.
    292       *bounds_in_out = top_window_state->GetRestoreBoundsInScreen() +
    293           gfx::Vector2d(kMinimumWindowOffset, kMinimumWindowOffset);
    294     }
    295     if (is_saved_bounds || has_restore_bounds) {
    296       gfx::Rect work_area = screen->GetDisplayNearestWindow(target).work_area();
    297       bounds_in_out->AdjustToFit(work_area);
    298       // Use adjusted saved bounds or restore bounds, if there is one.
    299       return;
    300     }
    301   }
    302 
    303   // Use the size of the other window. The window's bound will be rearranged
    304   // in ash::WorkspaceLayoutManager using this location.
    305   *bounds_in_out = top_window->GetBoundsInScreen();
    306 }
    307 
    308 // static
    309 void WindowPositioner::RearrangeVisibleWindowOnHideOrRemove(
    310     const aura::Window* removed_window) {
    311   if (!UseAutoWindowManager(removed_window))
    312     return;
    313   // Find a single open browser window.
    314   bool single_window;
    315   aura::Window* other_shown_window = GetReferenceWindow(
    316       removed_window->GetRootWindow(), removed_window, &single_window);
    317   if (!other_shown_window || !single_window ||
    318       !WindowPositionCanBeManaged(other_shown_window))
    319     return;
    320   AutoPlaceSingleWindow(other_shown_window, true);
    321 }
    322 
    323 // static
    324 bool WindowPositioner::DisableAutoPositioning(bool ignore) {
    325   bool old_state = disable_auto_positioning;
    326   disable_auto_positioning = ignore;
    327   return old_state;
    328 }
    329 
    330 // static
    331 void WindowPositioner::RearrangeVisibleWindowOnShow(
    332     aura::Window* added_window) {
    333   wm::WindowState* added_window_state = wm::GetWindowState(added_window);
    334   if (!added_window->TargetVisibility())
    335     return;
    336 
    337   if (!UseAutoWindowManager(added_window) ||
    338       added_window_state->bounds_changed_by_user()) {
    339     if (added_window_state->minimum_visibility()) {
    340       // Guarantee minimum visibility within the work area.
    341       gfx::Rect work_area = GetWorkAreaForWindowInParent(added_window);
    342       gfx::Rect bounds = added_window->bounds();
    343       gfx::Rect new_bounds = bounds;
    344       ash::wm::AdjustBoundsToEnsureMinimumWindowVisibility(work_area,
    345                                                            &new_bounds);
    346       if (new_bounds != bounds)
    347         added_window->SetBounds(new_bounds);
    348     }
    349     return;
    350   }
    351   // Find a single open managed window.
    352   bool single_window;
    353   aura::Window* other_shown_window = GetReferenceWindow(
    354       added_window->GetRootWindow(), added_window, &single_window);
    355 
    356   if (!other_shown_window) {
    357     // It could be that this window is the first window joining the workspace.
    358     if (!WindowPositionCanBeManaged(added_window) || other_shown_window)
    359       return;
    360     // Since we might be going from 0 to 1 window, we have to arrange the new
    361     // window to a good default.
    362     AutoPlaceSingleWindow(added_window, false);
    363     return;
    364   }
    365 
    366   gfx::Rect other_bounds = other_shown_window->bounds();
    367   gfx::Rect work_area = GetWorkAreaForWindowInParent(added_window);
    368   bool move_other_right =
    369       other_bounds.CenterPoint().x() > work_area.x() + work_area.width() / 2;
    370 
    371   // Push the other window to the size only if there are two windows left.
    372   if (single_window) {
    373     // When going from one to two windows both windows loose their
    374     // "positioned by user" flags.
    375     added_window_state->set_bounds_changed_by_user(false);
    376     wm::WindowState* other_window_state =
    377         wm::GetWindowState(other_shown_window);
    378     other_window_state->set_bounds_changed_by_user(false);
    379 
    380     if (WindowPositionCanBeManaged(other_shown_window)) {
    381       // Don't override pre auto managed bounds as the current bounds
    382       // may not be original.
    383       if (!other_window_state->pre_auto_manage_window_bounds())
    384         other_window_state->SetPreAutoManageWindowBounds(other_bounds);
    385 
    386       // Push away the other window after remembering its current position.
    387       if (MoveRectToOneSide(work_area, move_other_right, &other_bounds))
    388         SetBoundsAnimated(other_shown_window, other_bounds, work_area);
    389     }
    390   }
    391 
    392   // Remember the current location of the window if it's new and push
    393   // it also to the opposite location if needed.  Since it is just
    394   // being shown, we do not need to animate it.
    395   gfx::Rect added_bounds = added_window->bounds();
    396   if (!added_window_state->pre_auto_manage_window_bounds())
    397     added_window_state->SetPreAutoManageWindowBounds(added_bounds);
    398   if (MoveRectToOneSide(work_area, !move_other_right, &added_bounds))
    399     added_window->SetBounds(added_bounds);
    400 }
    401 
    402 WindowPositioner::WindowPositioner()
    403     : pop_position_offset_increment_x(0),
    404       pop_position_offset_increment_y(0),
    405       popup_position_offset_from_screen_corner_x(0),
    406       popup_position_offset_from_screen_corner_y(0),
    407       last_popup_position_x_(0),
    408       last_popup_position_y_(0) {
    409 }
    410 
    411 WindowPositioner::~WindowPositioner() {
    412 }
    413 
    414 gfx::Rect WindowPositioner::GetDefaultWindowBounds(
    415     const gfx::Display& display) {
    416   const gfx::Rect work_area = display.work_area();
    417   // There should be a 'desktop' border around the window at the left and right
    418   // side.
    419   int default_width = work_area.width() - 2 * kDesktopBorderSize;
    420   // There should also be a 'desktop' border around the window at the top.
    421   // Since the workspace excludes the tray area we only need one border size.
    422   int default_height = work_area.height() - kDesktopBorderSize;
    423   int offset_x = kDesktopBorderSize;
    424   if (default_width > kMaximumWindowWidth) {
    425     // The window should get centered on the screen and not follow the grid.
    426     offset_x = (work_area.width() - kMaximumWindowWidth) / 2;
    427     default_width = kMaximumWindowWidth;
    428   }
    429   return gfx::Rect(work_area.x() + offset_x,
    430                    work_area.y() + kDesktopBorderSize,
    431                    default_width,
    432                    default_height);
    433 }
    434 
    435 gfx::Rect WindowPositioner::GetPopupPosition(const gfx::Rect& old_pos) {
    436   int grid = kMinimumWindowOffset;
    437   popup_position_offset_from_screen_corner_x = grid;
    438   popup_position_offset_from_screen_corner_y = grid;
    439   if (!pop_position_offset_increment_x) {
    440     // When the popup position increment is 0, the last popup position
    441     // was not yet initialized.
    442     last_popup_position_x_ = popup_position_offset_from_screen_corner_x;
    443     last_popup_position_y_ = popup_position_offset_from_screen_corner_y;
    444   }
    445   pop_position_offset_increment_x = grid;
    446   pop_position_offset_increment_y = grid;
    447   // We handle the Multi monitor support by retrieving the active window's
    448   // work area.
    449   aura::Window* window = wm::GetActiveWindow();
    450   const gfx::Rect work_area = window && window->IsVisible() ?
    451       Shell::GetScreen()->GetDisplayNearestWindow(window).work_area() :
    452       Shell::GetScreen()->GetPrimaryDisplay().work_area();
    453   // Only try to reposition the popup when it is not spanning the entire
    454   // screen.
    455   if ((old_pos.width() + popup_position_offset_from_screen_corner_x >=
    456       work_area.width()) ||
    457       (old_pos.height() + popup_position_offset_from_screen_corner_y >=
    458        work_area.height()))
    459     return AlignPopupPosition(old_pos, work_area, grid);
    460   const gfx::Rect result = SmartPopupPosition(old_pos, work_area, grid);
    461   if (!result.IsEmpty())
    462     return AlignPopupPosition(result, work_area, grid);
    463   return NormalPopupPosition(old_pos, work_area);
    464 }
    465 
    466 // static
    467 void WindowPositioner::SetMaximizeFirstWindow(bool maximize) {
    468   maximize_first_window = maximize;
    469 }
    470 
    471 gfx::Rect WindowPositioner::NormalPopupPosition(
    472     const gfx::Rect& old_pos,
    473     const gfx::Rect& work_area) {
    474   int w = old_pos.width();
    475   int h = old_pos.height();
    476   // Note: The 'last_popup_position' is checked and kept relative to the
    477   // screen size. The offsetting will be done in the last step when the
    478   // target rectangle gets returned.
    479   bool reset = false;
    480   if (last_popup_position_y_ + h > work_area.height() ||
    481       last_popup_position_x_ + w > work_area.width()) {
    482     // Popup does not fit on screen. Reset to next diagonal row.
    483     last_popup_position_x_ -= last_popup_position_y_ -
    484                               popup_position_offset_from_screen_corner_x -
    485                               pop_position_offset_increment_x;
    486     last_popup_position_y_ = popup_position_offset_from_screen_corner_y;
    487     reset = true;
    488   }
    489   if (last_popup_position_x_ + w > work_area.width()) {
    490     // Start again over.
    491     last_popup_position_x_ = popup_position_offset_from_screen_corner_x;
    492     last_popup_position_y_ = popup_position_offset_from_screen_corner_y;
    493     reset = true;
    494   }
    495   int x = last_popup_position_x_;
    496   int y = last_popup_position_y_;
    497   if (!reset) {
    498     last_popup_position_x_ += pop_position_offset_increment_x;
    499     last_popup_position_y_ += pop_position_offset_increment_y;
    500   }
    501   return gfx::Rect(x + work_area.x(), y + work_area.y(), w, h);
    502 }
    503 
    504 gfx::Rect WindowPositioner::SmartPopupPosition(
    505     const gfx::Rect& old_pos,
    506     const gfx::Rect& work_area,
    507     int grid) {
    508   const std::vector<aura::Window*> windows =
    509       MruWindowTracker::BuildWindowList(false);
    510 
    511   std::vector<const gfx::Rect*> regions;
    512   // Process the window list and check if we can bail immediately.
    513   for (size_t i = 0; i < windows.size(); i++) {
    514     // We only include opaque and visible windows.
    515     if (windows[i] && windows[i]->IsVisible() && windows[i]->layer() &&
    516         (!windows[i]->transparent() ||
    517          windows[i]->layer()->GetTargetOpacity() == 1.0)) {
    518       wm::WindowState* window_state = wm::GetWindowState(windows[i]);
    519       // When any window is maximized we cannot find any free space.
    520       if (window_state->IsMaximizedOrFullscreen())
    521         return gfx::Rect(0, 0, 0, 0);
    522       if (window_state->IsNormalOrSnapped())
    523         regions.push_back(&windows[i]->bounds());
    524     }
    525   }
    526 
    527   if (regions.empty())
    528     return gfx::Rect(0, 0, 0, 0);
    529 
    530   int w = old_pos.width();
    531   int h = old_pos.height();
    532   int x_end = work_area.width() / 2;
    533   int x, x_increment;
    534   // We parse for a proper location on the screen. We do this in two runs:
    535   // The first run will start from the left, parsing down, skipping any
    536   // overlapping windows it will encounter until the popup's height can not
    537   // be served anymore. Then the next grid position to the right will be
    538   // taken, and the same cycle starts again. This will be repeated until we
    539   // hit the middle of the screen (or we find a suitable location).
    540   // In the second run we parse beginning from the right corner downwards and
    541   // then to the left.
    542   // When no location was found, an empty rectangle will be returned.
    543   for (int run = 0; run < 2; run++) {
    544     if (run == 0) { // First run: Start left, parse right till mid screen.
    545       x = 0;
    546       x_increment = pop_position_offset_increment_x;
    547     } else { // Second run: Start right, parse left till mid screen.
    548       x = work_area.width() - w;
    549       x_increment = -pop_position_offset_increment_x;
    550     }
    551     // Note: The passing (x,y,w,h) window is always relative to the work area's
    552     // origin.
    553     for (; x_increment > 0 ? (x < x_end) : (x > x_end); x += x_increment) {
    554       int y = 0;
    555       while (y + h <= work_area.height()) {
    556         size_t i;
    557         for (i = 0; i < regions.size(); i++) {
    558           if (regions[i]->Intersects(gfx::Rect(x + work_area.x(),
    559                                                y + work_area.y(), w, h))) {
    560             y = regions[i]->bottom() - work_area.y();
    561             break;
    562           }
    563         }
    564         if (i >= regions.size())
    565           return gfx::Rect(x + work_area.x(), y + work_area.y(), w, h);
    566       }
    567     }
    568   }
    569   return gfx::Rect(0, 0, 0, 0);
    570 }
    571 
    572 gfx::Rect WindowPositioner::AlignPopupPosition(
    573     const gfx::Rect& pos,
    574     const gfx::Rect& work_area,
    575     int grid) {
    576   if (grid <= 1)
    577     return pos;
    578 
    579   int x = pos.x() - (pos.x() - work_area.x()) % grid;
    580   int y = pos.y() - (pos.y() - work_area.y()) % grid;
    581   int w = pos.width();
    582   int h = pos.height();
    583 
    584   // If the alignment was pushing the window out of the screen, we ignore the
    585   // alignment for that call.
    586   if (abs(pos.right() - work_area.right()) < grid)
    587     x = work_area.right() - w;
    588   if (abs(pos.bottom() - work_area.bottom()) < grid)
    589     y = work_area.bottom() - h;
    590   return gfx::Rect(x, y, w, h);
    591 }
    592 
    593 }  // namespace ash
    594