cc: Send shared variables between main and impl side using the channel

cc/trees/proxy_impl.h

 // Copyright 2015 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_TREES_PROXY_IMPL_H_
 #define CC_TREES_PROXY_IMPL_H_
 
 #include "base/memory/weak_ptr.h"
 #include "cc/base/cc_export.h"
 #include "cc/base/completion_event.h"
@@ skipping 23 matching lines @@
   virtual void SetNeedsRedrawOnImpl(const gfx::Rect& damage_rect) = 0;
   virtual void SetNeedsCommitOnImpl() = 0;
   virtual void BeginMainFrameAbortedOnImpl(CommitEarlyOutReason reason) = 0;
   virtual void FinishAllRenderingOnImpl(CompletionEvent* completion) = 0;
   virtual void SetVisibleOnImpl(CompletionEvent* completion, bool visible) = 0;
   virtual void ReleaseOutputSurfaceOnImpl(CompletionEvent* completion) = 0;
   virtual void FinishGLOnImpl(CompletionEvent* completion) = 0;
   virtual void MainFrameWillHappenOnImplForTesting(
       CompletionEvent* completion,
       bool* main_frame_will_happen) = 0;
-  virtual void StartCommitOnImpl(CompletionEvent* completion) = 0;
+  virtual void StartCommitOnImpl(CompletionEvent* completion,
+                                 LayerTreeHost* layer_tree_host,
+                                 bool hold_commit_for_activation) = 0;
+  virtual void InitializeImplOnImpl(CompletionEvent* completion,
+                                    LayerTreeHost* layer_tree_host) = 0;
+  virtual void LayerTreeHostClosedOnImpl(CompletionEvent* completion) = 0;
 
   // TODO(khushalsagar): Rename as GetWeakPtr() once ThreadProxy is split.
   virtual base::WeakPtr<ProxyImpl> GetImplWeakPtr() = 0;
 
  protected:
   virtual ~ProxyImpl() {}
 };
 
 }  // namespace cc
 
 #endif  // CC_TREES_PROXY_IMPL_H_