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

cc/surfaces/surface.h

 // Copyright 2014 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_SURFACES_SURFACE_H_
 #define CC_SURFACES_SURFACE_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 36 matching lines @@
   SurfaceId previous_frame_surface_id() const {
     return previous_frame_surface_id_;
   }
 
   void SetPreviousFrameSurface(Surface* surface);
   void SetGpuMemoryBufferClientId(int gpu_memory_buffer_client_id);
   int gpu_memory_buffer_client_id() const {
     return gpu_memory_buffer_client_id_;
   }
 
-  void QueueFrame(std::unique_ptr<CompositorFrame> frame,
-                  const DrawCallback& draw_callback);
+  void QueueFrame(CompositorFrame frame, const DrawCallback& draw_callback);
   void RequestCopyOfOutput(std::unique_ptr<CopyOutputRequest> copy_request);
   // Adds each CopyOutputRequest in the current frame to copy_requests. The
   // caller takes ownership of them.
   void TakeCopyOutputRequests(
       std::multimap<RenderPassId, std::unique_ptr<CopyOutputRequest>>*
           copy_requests);
+
   // Returns the most recent frame that is eligible to be rendered.
-  const CompositorFrame* GetEligibleFrame();
+  // If the CompositorFrame's DelegateFrameData is null then there is
+  // no eligible frame.
+  const CompositorFrame& GetEligibleFrame();
 
   // Returns a number that increments by 1 every time a new frame is enqueued.
   int frame_index() const { return frame_index_; }
 
   void TakeLatencyInfo(std::vector<ui::LatencyInfo>* latency_info);
   void RunDrawCallbacks(SurfaceDrawStatus drawn);
 
   base::WeakPtr<SurfaceFactory> factory() { return factory_; }
 
   // Add a SurfaceSequence that must be satisfied before the Surface is
@@ skipping 18 matching lines @@
 
  private:
   void UnrefFrameResources(DelegatedFrameData* frame_data);
   void ClearCopyRequests();
 
   SurfaceId surface_id_;
   SurfaceId previous_frame_surface_id_;
   int gpu_memory_buffer_client_id_ = -1;
   base::WeakPtr<SurfaceFactory> factory_;
   // TODO(jamesr): Support multiple frames in flight.
-  std::unique_ptr<CompositorFrame> current_frame_;
+  CompositorFrame current_frame_;
   int frame_index_;
   bool destroyed_;
   std::vector<SurfaceSequence> destruction_dependencies_;
 
   // This surface may have multiple BeginFrameSources if it is
   // on multiple Displays.
   std::set<BeginFrameSource*> begin_frame_sources_;
 
   std::vector<SurfaceId> referenced_surfaces_;
 
   DrawCallback draw_callback_;
 
   DISALLOW_COPY_AND_ASSIGN(Surface);
 };
 
 }  // namespace cc
 
 #endif  // CC_SURFACES_SURFACE_H_