[cc] Route LayerImpl::layerTreeHostImpl() calls through LayerTreeImpl

cc/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_LAYER_IMPL_H_
 #define CC_LAYER_IMPL_H_
 
 #include <public/WebFilterOperations.h>
 #include <string>
 
@@ skipping 64 matching lines @@
 
     void setReplicaLayer(scoped_ptr<LayerImpl>);
     LayerImpl* replicaLayer() { return m_replicaLayer.get(); }
     const LayerImpl* replicaLayer() const { return m_replicaLayer.get(); }
 
     bool hasMask() const { return m_maskLayer; }
     bool hasReplica() const { return m_replicaLayer; }
     bool replicaHasMask() const { return m_replicaLayer && (m_maskLayer || m_replicaLayer->m_maskLayer); }
 
     LayerTreeImpl* layerTreeImpl() const { return m_layerTreeImpl; }
-    LayerTreeHostImpl* layerTreeHostImpl() const;
 
     scoped_ptr<SharedQuadState> createSharedQuadState() const;
     // willDraw must be called before appendQuads. If willDraw is called,
     // didDraw is guaranteed to be called before another willDraw or before
     // the layer is destroyed. To enforce this, any class that overrides
     // willDraw/didDraw must call the base class version.
     virtual void willDraw(ResourceProvider*);
     virtual void appendQuads(QuadSink&, AppendQuadsData&) { }
     virtual void didDraw(ResourceProvider*);
 
@@ skipping 309 matching lines @@
     // Group of properties that need to be computed based on the layer tree
     // hierarchy before layers can be drawn.
     DrawProperties<LayerImpl, RenderSurfaceImpl> m_drawProperties;
 
     DISALLOW_COPY_AND_ASSIGN(LayerImpl);
 };
 
 }
 
 #endif  // CC_LAYER_IMPL_H_