Never call GraphicsLayer::paint when fetching painted output from cc.

cc/layers/content_layer_client.h

 // 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.
 
 #ifndef CC_LAYERS_CONTENT_LAYER_CLIENT_H_
 #define CC_LAYERS_CONTENT_LAYER_CLIENT_H_
 
 #include <stddef.h>
 
 #include "cc/base/cc_export.h"
 #include "cc/playback/display_item_list.h"
 
 namespace gfx {
 class Rect;
 }
 
 namespace cc {
 
 class CC_EXPORT ContentLayerClient {
  public:
   enum PaintingControlSetting {
     PAINTING_BEHAVIOR_NORMAL,
+    PAINTING_BEHAVIOR_NORMAL_FOR_TEST,
     DISPLAY_LIST_CONSTRUCTION_DISABLED,
     DISPLAY_LIST_CACHING_DISABLED,
     DISPLAY_LIST_PAINTING_DISABLED,
     SUBSEQUENCE_CACHING_DISABLED,
   };
 
   // The paintable region is the rectangular region, within the bounds of the
   // layer this client paints, that the client is capable of painting via
   // paintContents(). Calling paintContents() will return a DisplayItemList
   // that is guaranteed valid only within this region.
@@ skipping 12 matching lines @@
   // so that the result includes data cached internally during painting.
   virtual size_t GetApproximateUnsharedMemoryUsage() const = 0;
 
  protected:
   virtual ~ContentLayerClient() {}
 };
 
 }  // namespace cc
 
 #endif  // CC_LAYERS_CONTENT_LAYER_CLIENT_H_