layers: Consolidate the ownership of layers in views::View and aura::Window.

ui/views/view.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 "ui/views/view.h"
 
 #include <algorithm>
 
 #include "base/debug/trace_event.h"
 #include "base/logging.h"
@@ skipping 438 matching lines @@
 
 void View::SetPaintToLayer(bool paint_to_layer) {
   paint_to_layer_ = paint_to_layer;
   if (paint_to_layer_ && !layer()) {
     CreateLayer();
   } else if (!paint_to_layer_ && layer()) {
     DestroyLayer();
   }
 }
 
+ui::Layer* View::RecreateLayer() {
+  ui::Layer* layer = AcquireLayer();
+  CreateLayer();
+  return layer;
+}
+
 // RTL positioning -------------------------------------------------------------
 
 gfx::Rect View::GetMirroredBounds() const {
   gfx::Rect bounds(bounds_);
   bounds.set_x(GetMirroredX());
   return bounds;
 }
 
 gfx::Point View::GetMirroredPosition() const {
   return gfx::Point(GetMirroredX(), y());
@@ skipping 1305 matching lines @@
 }
 
 // Accelerated painting --------------------------------------------------------
 
 void View::CreateLayer() {
   // A new layer is being created for the view. So all the layers of the
   // sub-tree can inherit the visibility of the corresponding view.
   for (int i = 0, count = child_count(); i < count; ++i)
     child_at(i)->UpdateChildLayerVisibility(true);
 
-  layer_.reset(new ui::Layer());
+  layer_ = new ui::Layer();
+  layer_owner_.reset(layer_);
   layer_->set_delegate(this);
 #if !defined(NDEBUG)
   layer_->set_name(GetClassName());
 #endif
 
   UpdateParentLayers();
   UpdateLayerVisibility();
 
   // The new layer needs to be ordered in the layer tree according
   // to the view tree. Children of this layer were added in order
@@ skipping 54 matching lines @@
 
 void View::DestroyLayer() {
   ui::Layer* new_parent = layer()->parent();
   std::vector<ui::Layer*> children = layer()->children();
   for (size_t i = 0; i < children.size(); ++i) {
     layer()->Remove(children[i]);
     if (new_parent)
       new_parent->Add(children[i]);
   }
 
-  layer_.reset();
+  layer_ = NULL;
+  layer_owner_.reset();
 
   if (new_parent)
     ReorderLayers();
 
   gfx::Point offset;
   CalculateOffsetToAncestorWithLayer(&offset, NULL);
   UpdateChildLayerBounds(offset);
 
   SchedulePaint();
 }
@@ skipping 199 matching lines @@
   gfx::Point widget_location(event.location());
   ConvertPointToWidget(this, &widget_location);
   GetWidget()->RunShellDrag(this, data, widget_location, drag_operations);
   return true;
 #else
   return false;
 #endif  // !defined(OS_MACOSX)
 }
 
 }  // namespace views