Make cc::CompositorFrames movable [Part 1 of 2]

cc/output/delegating_renderer.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_OUTPUT_DELEGATING_RENDERER_H_
 #define CC_OUTPUT_DELEGATING_RENDERER_H_
 
 #include <memory>
 
 #include "base/macros.h"
@@ skipping 18 matching lines @@
   const RendererCapabilitiesImpl& Capabilities() const override;
 
   void DrawFrame(RenderPassList* render_passes_in_draw_order,
                  float device_scale_factor,
                  const gfx::Rect& device_viewport_rect,
                  const gfx::Rect& device_clip_rect,
                  bool disable_picture_quad_image_filtering) override;
 
   void Finish() override {}
 
-  void SwapBuffers(const CompositorFrameMetadata& metadata) override;
+  void SwapBuffers(CompositorFrameMetadata metadata) override;
   void ReceiveSwapBuffersAck(const CompositorFrameAck&) override;
 
  private:
   DelegatingRenderer(RendererClient* client,
                      const RendererSettings* settings,
                      OutputSurface* output_surface,
                      ResourceProvider* resource_provider);
 
   void DidChangeVisibility() override;
 
   OutputSurface* output_surface_;
   ResourceProvider* resource_provider_;
   RendererCapabilitiesImpl capabilities_;
   std::unique_ptr<DelegatedFrameData> delegated_frame_data_;
 
   DISALLOW_COPY_AND_ASSIGN(DelegatingRenderer);
 };
 
 }  // namespace cc
 
 #endif  // CC_OUTPUT_DELEGATING_RENDERER_H_