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

cc/test/fake_output_surface.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_TEST_FAKE_OUTPUT_SURFACE_H_
 #define CC_TEST_FAKE_OUTPUT_SURFACE_H_
 
 #include <stddef.h>
 
 #include "base/callback.h"
@@ skipping 91 matching lines @@
         new FakeOutputSurface(TestContextProvider::Create(std::move(context)),
                               TestContextProvider::CreateWorker(), false));
     surface->capabilities_.uses_default_gl_framebuffer = false;
     return surface;
   }
 
   void set_max_frames_pending(int max) {
     capabilities_.max_frames_pending = max;
   }
 
-  CompositorFrame& last_sent_frame() { return last_sent_frame_; }
+  CompositorFrame* last_sent_frame() { return last_sent_frame_.get(); }
   size_t num_sent_frames() { return num_sent_frames_; }
 
-  void SwapBuffers(CompositorFrame* frame) override;
+  void SwapBuffers(CompositorFrame frame) override;
 
   OutputSurfaceClient* client() { return client_; }
   bool BindToClient(OutputSurfaceClient* client) override;
 
   void set_framebuffer(GLint framebuffer, GLenum format) {
     framebuffer_ = framebuffer;
     framebuffer_format_ = format;
   }
   void BindFramebuffer() override;
   uint32_t GetFramebufferCopyTextureFormat() override;
@@ skipping 37 matching lines @@
 
   FakeOutputSurface(std::unique_ptr<SoftwareOutputDevice> software_device,
                     bool delegated_rendering);
 
   FakeOutputSurface(scoped_refptr<ContextProvider> context_provider,
                     scoped_refptr<ContextProvider> worker_context_provider,
                     std::unique_ptr<SoftwareOutputDevice> software_device,
                     bool delegated_rendering);
 
   OutputSurfaceClient* client_ = nullptr;
-  CompositorFrame last_sent_frame_;
+  std::unique_ptr<CompositorFrame> last_sent_frame_;
   size_t num_sent_frames_ = 0;
   bool has_external_stencil_test_ = false;
   bool suspended_for_recycle_ = false;
   GLint framebuffer_ = 0;
   GLenum framebuffer_format_ = 0;
   TransferableResourceArray resources_held_by_parent_;
   std::unique_ptr<ManagedMemoryPolicy> memory_policy_to_set_at_bind_;
   OverlayCandidateValidator* overlay_candidate_validator_ = nullptr;
   gfx::Rect last_swap_rect_;
 };
 
 }  // namespace cc
 
 #endif  // CC_TEST_FAKE_OUTPUT_SURFACE_H_