cc: Remove OutputSurfaceClient::DidSwapBuffers().

cc/test/pixel_test_delegating_output_surface.cc

 // 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.
 
 #include "cc/test/pixel_test_delegating_output_surface.h"
 
 #include <stdint.h>
 #include <memory>
 #include <utility>
 
@@ skipping 104 matching lines @@
 
   display_ = nullptr;
   surface_factory_ = nullptr;
   surface_id_allocator_ = nullptr;
   surface_manager_ = nullptr;
   weak_ptrs_.InvalidateWeakPtrs();
   OutputSurface::DetachFromClient();
 }
 
 void PixelTestDelegatingOutputSurface::SwapBuffers(CompositorFrame frame) {
-  client_->DidSwapBuffers();
-
   if (delegated_surface_id_.is_null()) {
     delegated_surface_id_ = surface_id_allocator_->GenerateId();
     surface_factory_->Create(delegated_surface_id_);
   }
   display_->SetSurfaceId(delegated_surface_id_,
                          frame.metadata.device_scale_factor);
 
   gfx::Size frame_size =
       frame.delegated_frame_data->render_pass_list.back()->output_rect.size();
   display_->Resize(frame_size);
@@ skipping 42 matching lines @@
   ack.resources = resources;
   client_->ReclaimResources(&ack);
 }
 
 void PixelTestDelegatingOutputSurface::SetBeginFrameSource(
     BeginFrameSource* begin_frame_source) {
   client_->SetBeginFrameSource(begin_frame_source);
 }
 
 }  // namespace cc