Use surface copy requests for layout tests.

content/renderer/gpu/render_widget_compositor.h

 // Copyright (c) 2013 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 CONTENT_RENDERER_GPU_RENDER_WIDGET_COMPOSITOR_H_
 #define CONTENT_RENDERER_GPU_RENDER_WIDGET_COMPOSITOR_H_
 
 #include <stdint.h>
 
 #include "base/callback.h"
@@ skipping 201 matching lines @@
   void SynchronouslyComposite();
 
   int num_failed_recreate_attempts_;
   RenderWidgetCompositorDelegate* const delegate_;
   CompositorDependencies* const compositor_deps_;
   const bool threaded_;
   std::unique_ptr<cc::LayerTreeHost> layer_tree_host_;
   bool never_visible_;
 
   blink::WebLayoutAndPaintAsyncCallback* layout_and_paint_async_callback_;
-  std::unique_ptr<cc::CopyOutputRequest> temporary_copy_output_request_;
 
   cc::RemoteProtoChannel::ProtoReceiver* remote_proto_channel_receiver_;
 
   base::WeakPtrFactory<RenderWidgetCompositor> weak_factory_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_GPU_RENDER_WIDGET_COMPOSITOR_H_