Activate LayerImpl tree with sync+push instead of pointer swap

cc/layer_tree_impl.h

 // Copyright 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.
 
 #ifndef CC_LAYER_TREE_IMPL_H_
 #define CC_LAYER_TREE_IMPL_H_
 
 #include "base/hash_tables.h"
 #include "cc/layer_impl.h"
 
@@ skipping 37 matching lines @@
   // Methods called by the layer tree that pass-through or access LTHI.
   // ---------------------------------------------------------------------------
   const LayerTreeSettings& settings() const;
   OutputSurface* output_surface() const;
   ResourceProvider* resource_provider() const;
   TileManager* tile_manager() const;
   FrameRateCounter* frame_rate_counter() const;
   PaintTimeCounter* paint_time_counter() const;
   bool IsActiveTree() const;
   bool IsPendingTree() const;
+  bool IsRecycleTree() const;
   LayerImpl* FindActiveTreeLayerById(int id);
   LayerImpl* FindPendingTreeLayerById(int id);
   int MaxTextureSize() const;
   bool PinchGestureActive() const;
 
   // Tree specific methods exposed to layer-impl tree.
   // ---------------------------------------------------------------------------
   void SetNeedsRedraw();
   void SetNeedsUpdateDrawProperties();
 
@@ skipping 64 matching lines @@
   AnimationRegistrar* animationRegistrar() const;
 
   void PushPersistedState(LayerTreeImpl* pendingTree);
 
   void DidBecomeActive();
 
   bool ContentsTexturesPurged() const;
   void SetContentsTexturesPurged();
   void ResetContentsTexturesPurged();
 
+  // Useful for debug assertions, probably shouldn't be used for anything else.
+  Proxy* proxy() const;
+
 protected:
   LayerTreeImpl(LayerTreeHostImpl* layer_tree_host_impl);
 
   LayerTreeHostImpl* layer_tree_host_impl_;
   int source_frame_number_;
   scoped_ptr<LayerImpl> root_layer_;
   HeadsUpDisplayLayerImpl* hud_layer_;
   LayerImpl* root_scroll_layer_;
   LayerImpl* currently_scrolling_layer_;
   SkColor background_color_;
@@ skipping 10 matching lines @@
   LayerList render_surface_layer_list_;
 
   bool contents_textures_purged_;
 
   DISALLOW_COPY_AND_ASSIGN(LayerTreeImpl);
 };
 
 }
 
 #endif  // CC_LAYER_TREE_IMPL_H_