cc: Change required_for_activation bookkeeping.

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 <set>
 #include <string>
 
@@ skipping 33 matching lines @@
 
 namespace cc {
 
 class LayerTreeHostImpl;
 class LayerTreeImpl;
 class MicroBenchmarkImpl;
 class QuadSink;
 class Renderer;
 class ScrollbarAnimationController;
 class ScrollbarLayerImplBase;
+class Tile;
 
 struct AppendQuadsData;
 
 enum DrawMode {
   DRAW_MODE_NONE,
   DRAW_MODE_HARDWARE,
   DRAW_MODE_SOFTWARE,
   DRAW_MODE_RESOURCELESS_SOFTWARE
 };
 
@@ skipping 107 matching lines @@
   virtual void DidDraw(ResourceProvider* resource_provider);
 
   virtual ResourceProvider::ResourceId ContentsResourceId() const;
 
   virtual bool HasDelegatedContent() const;
   virtual bool HasContributingDelegatedRenderPasses() const;
   virtual RenderPass::Id FirstContributingRenderPassId() const;
   virtual RenderPass::Id NextContributingRenderPassId(RenderPass::Id id) const;
 
   virtual void UpdateTilePriorities() {}
+  virtual void NotifyTileInitialized(const Tile* tile) {}
 
   virtual ScrollbarLayerImplBase* ToScrollbarLayer();
 
   // Returns true if this layer has content to draw.
   void SetDrawsContent(bool draws_content);
   bool DrawsContent() const { return draws_content_; }
 
   void SetHideLayerAndSubtree(bool hide);
   bool hide_layer_and_subtree() const { return hide_layer_and_subtree_; }
 
@@ skipping 482 matching lines @@
   DrawProperties<LayerImpl> draw_properties_;
 
   scoped_refptr<base::debug::ConvertableToTraceFormat> debug_info_;
 
   DISALLOW_COPY_AND_ASSIGN(LayerImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_LAYERS_LAYER_IMPL_H_