[Athena] Fix potential crash when overview window is deleted

athena/wm/window_overview_mode.cc

 // Copyright 2014 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 "athena/wm/window_overview_mode.h"
 
 #include <algorithm>
 #include <functional>
 #include <vector>
 
@@ skipping 10 matching lines @@
 #include "ui/aura/window_tree_host.h"
 #include "ui/compositor/closure_animation_observer.h"
 #include "ui/compositor/compositor.h"
 #include "ui/compositor/compositor_animation_observer.h"
 #include "ui/compositor/scoped_layer_animation_settings.h"
 #include "ui/events/event_handler.h"
 #include "ui/events/gestures/fling_curve.h"
 #include "ui/gfx/frame_time.h"
 #include "ui/gfx/transform.h"
 #include "ui/wm/core/shadow_types.h"
+#include "ui/wm/core/window_animations.h"
 #include "ui/wm/core/window_util.h"
 
 namespace {
 
 struct WindowOverviewState {
   // The transform for when the window is at the topmost position.
   gfx::Transform top;
 
   // The transform for when the window is at the bottom-most position.
   gfx::Transform bottom;
@@ skipping 431 matching lines @@
     const bool swipe_towards_right = event.details().velocity_x() > 0;
     if (dragging_towards_right != swipe_towards_right)
       return false;
     const float kMinVelocityForDismissal = 500.f;
     return std::abs(event.details().velocity_x()) > kMinVelocityForDismissal;
   }
 
   void CloseDragWindow(const ui::GestureEvent& gesture) {
     // Animate |dragged_window_| offscreen first, then destroy it.
     {
-      ui::ScopedLayerAnimationSettings settings(
-          dragged_window_->layer()->GetAnimator());
-      settings.SetPreemptionStrategy(
+      wm::ScopedHidingAnimationSettings settings(dragged_window_);
+      settings.layer_animation_settings()->SetPreemptionStrategy(
           ui::LayerAnimator::IMMEDIATELY_ANIMATE_TO_NEW_TARGET);
-      settings.AddObserver(new ui::ClosureAnimationObserver(
-          base::Bind(&base::DeletePointer<aura::Window>, dragged_window_)));
 
       WindowOverviewState* dragged_state =
           dragged_window_->GetProperty(kWindowOverviewState);
       CHECK(dragged_state);
       gfx::Transform transform = dragged_window_->layer()->transform();
       gfx::RectF transformed_bounds = dragged_window_->bounds();
       transform.TransformRect(&transformed_bounds);
       float transform_x = 0.f;
       if (gesture.location().x() > dragged_start_location_.x())
         transform_x = container_->bounds().right() - transformed_bounds.x();
@@ skipping 41 matching lines @@
 
         aura::Window* next = *(iter + 1);
         WindowOverviewState* next_state =
             next->GetProperty(kWindowOverviewState);
         UpdateTerminalStateForWindowAtIndex(
             window, list.end() - iter, list.size());
         SetWindowProgress(window, next_state->progress);
       }
     }
 
+    delete dragged_window_;
     dragged_window_ = NULL;
   }
 
   void RestoreDragWindow() {
     CHECK(dragged_window_);
     WindowOverviewState* dragged_state =
         dragged_window_->GetProperty(kWindowOverviewState);
     CHECK(dragged_state);
 
     ui::ScopedLayerAnimationSettings settings(
@@ skipping 188 matching lines @@
     aura::Window* container,
     const WindowListProvider* window_list_provider,
     SplitViewController* split_view_controller,
     WindowOverviewModeDelegate* delegate) {
   return scoped_ptr<WindowOverviewMode>(
       new WindowOverviewModeImpl(container, window_list_provider,
                                  split_view_controller, delegate));
 }
 
 }  // namespace athena