cc: Async readback.

cc/layers/layer_impl.h

 // Copyright 2011 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.
 
 #ifndef CC_LAYERS_LAYER_IMPL_H_
 #define CC_LAYERS_LAYER_IMPL_H_
 
 #include <string>
 
 #include "base/logging.h"
@@ skipping 57 matching lines @@
   const LayerImpl* parent() const { return parent_; }
   const OwnedLayerImplList& children() const { return children_; }
   OwnedLayerImplList& children() { return children_; }
   LayerImpl* child_at(size_t index) const { return children_[index]; }
   void AddChild(scoped_ptr<LayerImpl> child);
   scoped_ptr<LayerImpl> RemoveChild(LayerImpl* child);
   void set_parent(LayerImpl* parent) { parent_ = parent; }
   // Warning: This does not preserve tree structure invariants.
   void ClearChildList();
 
+  void PassRequestCopyCallbacks(
+      std::vector<RenderPass::RequestCopyAsBitmapCallback>* callbacks);
+  void TakeRequestCopyCallbacks(
+      std::vector<RenderPass::RequestCopyAsBitmapCallback>* callbacks);
+  bool HasRequestCopyCallback() const {
+    return !request_copy_callbacks_.empty();
+  }
+
   void SetMaskLayer(scoped_ptr<LayerImpl> mask_layer);
   LayerImpl* mask_layer() { return mask_layer_.get(); }
   const LayerImpl* mask_layer() const { return mask_layer_.get(); }
   scoped_ptr<LayerImpl> TakeMaskLayer();
 
   void SetReplicaLayer(scoped_ptr<LayerImpl> replica_layer);
   LayerImpl* replica_layer() { return replica_layer_.get(); }
   const LayerImpl* replica_layer() const { return replica_layer_.get(); }
   scoped_ptr<LayerImpl> TakeReplicaLayer();
 
@@ skipping 434 matching lines @@
   scoped_refptr<LayerAnimationController> layer_animation_controller_;
 
   // Manages scrollbars for this layer
   scoped_ptr<ScrollbarAnimationController> scrollbar_animation_controller_;
 
   // Weak pointers to this layer's scrollbars, if it has them. Updated during
   // tree synchronization.
   ScrollbarLayerImpl* horizontal_scrollbar_layer_;
   ScrollbarLayerImpl* vertical_scrollbar_layer_;
 
+  std::vector<RenderPass::RequestCopyAsBitmapCallback> request_copy_callbacks_;
+
   // Group of properties that need to be computed based on the layer tree
   // hierarchy before layers can be drawn.
   DrawProperties<LayerImpl, RenderSurfaceImpl> draw_properties_;
 
   DISALLOW_COPY_AND_ASSIGN(LayerImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_LAYERS_LAYER_IMPL_H_