[cc] Pass on BeginFrameAcks from CompositorEBFS through RWHVAura, DFH.

content/renderer/gpu/renderer_compositor_frame_sink.cc

 // Copyright (c) 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.
 
 #include "content/renderer/gpu/renderer_compositor_frame_sink.h"
 
 #include <utility>
 
 #include "base/command_line.h"
 #include "base/location.h"
@@ skipping 91 matching lines @@
   begin_frame_source_ = nullptr;
   compositor_frame_sink_proxy_->ClearCompositorFrameSink();
   compositor_frame_sink_filter_->RemoveHandlerOnCompositorThread(
       routing_id_, compositor_frame_sink_filter_handler_);
 
   cc::CompositorFrameSink::DetachFromClient();
 }
 
 void RendererCompositorFrameSink::SubmitCompositorFrame(
     cc::CompositorFrame frame) {
+  // We should only submit CompositorFrames with valid BeginFrameAcks.
+  DCHECK_LE(cc::BeginFrameArgs::kStartingFrameNumber,
+            frame.metadata.begin_frame_ack.sequence_number);
   {
     std::unique_ptr<FrameSwapMessageQueue::SendMessageScope>
         send_message_scope =
             frame_swap_message_queue_->AcquireSendMessageScope();
     std::vector<std::unique_ptr<IPC::Message>> messages;
     std::vector<IPC::Message> messages_to_deliver_with_frame;
     frame_swap_message_queue_->DrainMessages(&messages);
     FrameSwapMessageQueue::TransferMessages(&messages,
                                             &messages_to_deliver_with_frame);
     Send(new ViewHostMsg_SwapCompositorFrame(routing_id_,
@@ skipping 23 matching lines @@
   client_->ReclaimResources(resources);
   if (is_swap_ack)
     client_->DidReceiveCompositorFrameAck();
 }
 
 bool RendererCompositorFrameSink::Send(IPC::Message* message) {
   return message_sender_->Send(message);
 }
 
 }  // namespace content