Get rid of virtual Display::CreateScheduler.

cc/test/pixel_test_delegating_output_surface.h

 // Copyright 2016 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_PIXEL_TEST_DELEGATING_OUTPUT_SURFACE_H_
 #define CC_TEST_PIXEL_TEST_DELEGATING_OUTPUT_SURFACE_H_
 
 #include "base/memory/weak_ptr.h"
 #include "cc/output/output_surface.h"
 #include "cc/scheduler/begin_frame_source.h"
@@ skipping 41 matching lines @@
     void DisplaySetMemoryPolicy(const ManagedMemoryPolicy& policy) override {}
   };
 
   SharedBitmapManager* const shared_bitmap_manager_;
   gpu::GpuMemoryBufferManager* const gpu_memory_buffer_manager_;
   const bool allow_force_reclaim_resources_;
   const bool synchronous_composite_;
 
   gfx::Size enlarge_pass_texture_amount_;
 
-  std::unique_ptr<BackToBackBeginFrameSource> begin_frame_source_;
-
   // TODO(danakj): These don't to be stored in unique_ptrs when OutputSurface
   // is owned/destroyed on the compositor thread.
   std::unique_ptr<SurfaceManager> surface_manager_;
   std::unique_ptr<SurfaceIdAllocator> surface_id_allocator_;
   SurfaceId delegated_surface_id_;
 
   // Uses surface_manager_.
   std::unique_ptr<SurfaceFactory> surface_factory_;
 
   PixelTestDisplayClient display_client_;
   // Uses surface_manager_.
   std::unique_ptr<Display> display_;
 
   base::WeakPtrFactory<PixelTestDelegatingOutputSurface> weak_ptrs_;
 };
 
 }  // namespace cc
 
 #endif  // CC_TEST_PIXEL_TEST_DELEGATING_OUTPUT_SURFACE_H_