Fix layer leak in SystemTrayBubble

ash/system/tray/system_tray_bubble.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/system/tray/system_tray_bubble.h"
 
 #include "ash/shell.h"
 #include "ash/system/tray/system_tray.h"
 #include "ash/system/tray/system_tray_delegate.h"
 #include "ash/system/tray/system_tray_item.h"
@@ skipping 136 matching lines @@
 
 void SystemTrayBubble::UpdateView(
     const std::vector<ash::SystemTrayItem*>& items,
     BubbleType bubble_type) {
   DCHECK(bubble_type != BUBBLE_TYPE_NOTIFICATION);
   DCHECK(bubble_type != bubble_type_);
 
   const int kSwipeDelayMS = 150;
   base::TimeDelta swipe_duration =
       base::TimeDelta::FromMilliseconds(kSwipeDelayMS);
+  bool delete_layer = true;
   ui::Layer* layer = bubble_view_->RecreateLayer();

[sadrul, 2012/12/19 23:50:33]

Does it make sense to make |layer| a scoped_ptr, and then do a release() when
creating AnimationObserverDeleteLayer?

[oshima, 2012/12/20 00:05:19]

As I mentioned in the bug description, layer is being used after it's passed to
AnimationObserverDeleteLayer, so
I can't simply do new AnimationObserverDeleteLayer(layer.release());

I tried Pass(), but it didnt' work either.

[sadrul, 2012/12/20 00:08:01]

release() wouldn't destroy the layer, right? So it should be OK for it to be
used in AnimationObserverDeleteLayer?

   DCHECK(layer);
   layer->SuppressPaint();
 
   // When transitioning from detailed view to default view, animate the existing
   // view (slide out towards the right).
   if (bubble_type == BUBBLE_TYPE_DEFAULT) {
     // Make sure the old view is visibile over the new view during the
     // animation.
     layer->parent()->StackAbove(layer, bubble_view_->layer());
     ui::ScopedLayerAnimationSettings settings(layer->GetAnimator());
+    delete_layer = false;
     settings.AddObserver(new AnimationObserverDeleteLayer(layer));
     settings.SetTransitionDuration(swipe_duration);
     settings.SetTweenType(ui::Tween::EASE_OUT);
     gfx::Transform transform;
     transform.Translate(layer->bounds().width(), 0.0);
     layer->SetTransform(transform);
   }
 
   {
     // Add a shadow layer to make the old layer darker as the animation
@@ skipping 22 matching lines @@
   DestroyItemViews();
   bubble_view_->RemoveAllChildViews(true);
 
   items_ = items;
   bubble_type_ = bubble_type;
   CreateItemViews(
       Shell::GetInstance()->system_tray_delegate()->GetUserLoginStatus());
 
   // Close bubble view if we failed to create the item view.
   if (!bubble_view_->has_children()) {
+    if (delete_layer)
+      delete layer;
     Close();
     return;
   }
 
   bubble_view_->GetWidget()->GetContentsView()->Layout();
   // Make sure that the bubble is large enough for the default view.
   if (bubble_type_ == BUBBLE_TYPE_DEFAULT) {
     bubble_view_->SetMaxHeight(0);  // Clear max height limit.
   }
 
   // When transitioning from default view to detailed view, animate the new
   // view (slide in from the right).
   if (bubble_type == BUBBLE_TYPE_DETAILED) {
     ui::Layer* new_layer = bubble_view_->layer();
     gfx::Rect bounds = new_layer->bounds();
     gfx::Transform transform;
     transform.Translate(bounds.width(), 0.0);
     new_layer->SetTransform(transform);
     {
       ui::ScopedLayerAnimationSettings settings(new_layer->GetAnimator());
+      delete_layer = false;
       settings.AddObserver(new AnimationObserverDeleteLayer(layer));
       settings.SetTransitionDuration(swipe_duration);
       settings.SetTweenType(ui::Tween::EASE_OUT);
       new_layer->SetTransform(gfx::Transform());
     }
   }
+  if (delete_layer)
+    delete layer;
 }
 
 void SystemTrayBubble::InitView(views::View* anchor,
                                 user::LoginStatus login_status,
                                 TrayBubbleView::InitParams* init_params) {
   DCHECK(bubble_view_ == NULL);
 
   if (bubble_type_ == BUBBLE_TYPE_DETAILED &&
       init_params->max_height < kDetailedBubbleMaxHeight) {
     init_params->max_height = kDetailedBubbleMaxHeight;
@@ skipping 95 matching lines @@
       bool is_default_bubble = bubble_type_ == BUBBLE_TYPE_DEFAULT;
       bubble_view_->AddChildView(new TrayPopupItemContainer(
           view, is_default_bubble,
           is_default_bubble && (i < items_.size() - 2)));
     }
   }
 }
 
 }  // namespace internal
 }  // namespace ash