[exp] cc: Introduce cc::CompositorMutator.

cc/test/fake_layer_tree_host_impl.cc

 // 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.
 
 #include "cc/test/begin_frame_args_test.h"
 #include "cc/test/fake_layer_tree_host_impl.h"
 #include "cc/test/test_shared_bitmap_manager.h"
 #include "cc/trees/layer_tree_impl.h"
 
 namespace cc {
 
 FakeLayerTreeHostImpl::FakeLayerTreeHostImpl(Proxy* proxy,
                                              SharedBitmapManager* manager)
     : LayerTreeHostImpl(LayerTreeSettings(),
                         &client_,
                         proxy,
                         &stats_instrumentation_,
                         manager,
                         NULL,
+                        NULL,
                         0) {
   // Explicitly clear all debug settings.
   SetDebugState(LayerTreeDebugState());
   SetViewportSize(gfx::Size(100, 100));
 
   // Avoid using Now() as the frame time in unit tests.
   base::TimeTicks time_ticks = base::TimeTicks::FromInternalValue(1);
   SetCurrentBeginFrameArgs(
       CreateBeginFrameArgsForTesting(BEGINFRAME_FROM_HERE, time_ticks));
 }
 
 FakeLayerTreeHostImpl::FakeLayerTreeHostImpl(const LayerTreeSettings& settings,
                                              Proxy* proxy,
                                              SharedBitmapManager* manager)
     : LayerTreeHostImpl(settings,
                         &client_,
                         proxy,
                         &stats_instrumentation_,
                         manager,
                         NULL,
+                        NULL,
                         0) {
   // Explicitly clear all debug settings.
   SetDebugState(LayerTreeDebugState());
 
   // Avoid using Now() as the frame time in unit tests.
   base::TimeTicks time_ticks = base::TimeTicks::FromInternalValue(1);
   SetCurrentBeginFrameArgs(
       CreateBeginFrameArgsForTesting(BEGINFRAME_FROM_HERE, time_ticks));
 }
 
@@ skipping 34 matching lines @@
 }
 
 void FakeLayerTreeHostImpl::UpdateNumChildrenAndDrawProperties(
     LayerTreeImpl* layerTree) {
   RecursiveUpdateNumChildren(layerTree->root_layer());
   bool update_lcd_text = false;
   layerTree->UpdateDrawProperties(update_lcd_text);
 }
 
 }  // namespace cc