Restores maximized browser before dragging a tab

ash/wm/window_animations.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ash/wm/window_animations.h"
 
 #include <math.h>
 
 #include <algorithm>
 #include <vector>
@@ skipping 306 matching lines @@
 // |pause_duration| is the duration to pause at the current bounds before
 // animating. Returns the duration of the fade.
 base::TimeDelta CrossFadeImpl(aura::Window* window,
                               ui::Layer* old_layer,
                               gfx::Tween::Type tween_type) {
   const gfx::Rect old_bounds(old_layer->bounds());
   const gfx::Rect new_bounds(window->bounds());
   const bool old_on_top = (old_bounds.width() > new_bounds.width());
 
   // Shorten the animation if there's not much visual movement.
-  const base::TimeDelta duration = GetCrossFadeDuration(old_bounds, new_bounds);
+  const base::TimeDelta duration = GetCrossFadeDuration(window,
+                                                        old_bounds, new_bounds);
 
   // Scale up the old layer while translating to new position.
   {
     old_layer->GetAnimator()->StopAnimating();
     ui::ScopedLayerAnimationSettings settings(old_layer->GetAnimator());
 
     // Animation observer owns the old layer and deletes itself.
     settings.AddObserver(new CrossFadeObserver(window, old_layer));
     settings.SetTransitionDuration(duration);
     settings.SetTweenType(tween_type);
@@ skipping 85 matching lines @@
   layer_parent->Add(old_layer);
   const bool restoring = old_layer->bounds().width() > window->bounds().width();
   if (restoring)
     layer_parent->StackAbove(old_layer, new_workspace->layer());
   else
     layer_parent->StackBelow(old_layer, new_workspace->layer());
 
   CrossFadeImpl(window, old_layer, kCrossFadeTweenType);
 }
 
-base::TimeDelta GetCrossFadeDuration(const gfx::Rect& old_bounds,
+base::TimeDelta GetCrossFadeDuration(aura::Window* window,
+                                     const gfx::Rect& old_bounds,
                                      const gfx::Rect& new_bounds) {
-  if (views::corewm::WindowAnimationsDisabled(NULL))
+  if (views::corewm::WindowAnimationsDisabled(window))
     return base::TimeDelta();
 
   int old_area = old_bounds.width() * old_bounds.height();
   int new_area = new_bounds.width() * new_bounds.height();
   int max_area = std::max(old_area, new_area);
   // Avoid divide by zero.
   if (max_area == 0)
     return base::TimeDelta::FromMilliseconds(kCrossFadeDurationMS);
 
   int delta_area = std::abs(old_area - new_area);
@@ skipping 107 matching lines @@
   }
 
   // Assume the launcher is overflowed, zoom off to the bottom right of the
   // work area.
   gfx::Rect work_area =
       Shell::GetScreen()->GetDisplayNearestWindow(window).work_area();
   return gfx::Rect(work_area.right(), work_area.bottom(), 0, 0);
 }
 
 }  // namespace ash