compositor-worker: Initialize CW machinery plumbing to compositor and fire CW rAF callbacks.

cc/trees/threaded_channel.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_THREADED_CHANNEL_H_
 #define CC_TREES_THREADED_CHANNEL_H_
 
 #include <memory>
 
 #include "base/macros.h"
@@ skipping 70 matching lines @@
       ProxyMain* proxy_main,
       TaskRunnerProvider* task_runner_provider);
 
   ~ThreadedChannel() override;
 
   // ChannelMain Implementation
   void UpdateTopControlsStateOnImpl(TopControlsState constraints,
                                     TopControlsState current,
                                     bool animate) override;
   void InitializeOutputSurfaceOnImpl(OutputSurface* output_surface) override;
+  void InitializeMutatorOnImpl(LayerTreeMutator* mutator) override;
   void MainThreadHasStoppedFlingingOnImpl() override;
   void SetInputThrottledUntilCommitOnImpl(bool is_throttled) override;
   void SetDeferCommitsOnImpl(bool defer_commits) override;
   void SetNeedsCommitOnImpl() override;
   void BeginMainFrameAbortedOnImpl(
       CommitEarlyOutReason reason,
       base::TimeTicks main_thread_start_time) override;
   void SetNeedsRedrawOnImpl(const gfx::Rect& damage_rect) override;
   void SetVisibleOnImpl(bool visible) override;
 
@@ skipping 107 matching lines @@
   // Used on the main thread to safely queue calls to ProxyImpl to be run on the
   // impl thread.
   base::WeakPtr<ProxyImpl> proxy_impl_weak_ptr_;
 
   DISALLOW_COPY_AND_ASSIGN(ThreadedChannel);
 };
 
 }  // namespace cc
 
 #endif  // CC_TREES_THREADED_CHANNEL_H_