Implement video frame acknowledgements in the chromoting protocol.

remoting/protocol/client_video_dispatcher.h

Index: remoting/protocol/client_video_dispatcher.h
diff --git a/remoting/protocol/client_video_dispatcher.h b/remoting/protocol/client_video_dispatcher.h
index b2b1e3162ab5b08fb2317fe3e00ed3d02ae2bbcf..7b21f53193efb3c7d3cb0423a6cbe7260c4340a2 100644
--- a/remoting/protocol/client_video_dispatcher.h
+++ b/remoting/protocol/client_video_dispatcher.h
@@ -21,6 +21,13 @@ class ClientVideoDispatcher : public ChannelDispatcherBase {
   ~ClientVideoDispatcher() override;
 
  private:
+  void OnVideoPacket(scoped_ptr<VideoPacket> video_packet,
+                     const base::Closure& done);
+  void OnPacketProcessed(VideoAck ack_message,

[Wez, 2015/01/21 01:35:39]

const&

(Bind() should still copy the parameter into the closure, but you'll avoid an
extra copy when it is Run())

[Sergey Ulanov, 2015/01/29 01:33:28]

Done.

+                         base::TimeTicks received_time,
+                         const base::Closure& done);

[Wez, 2015/01/21 01:35:39]

Suggest more helpful naming, e.g. OnVideoPacket->ProcessVideoPacket and
OnPacketProcessed->AcknowledgeVideoPacket.

Or if you prefer to keep the names generic-sounding then add comments to explain
their purpose.

[Sergey Ulanov, 2015/01/29 01:33:28]

Renamed OnVideoPacket() only. OnPacketProcessed() is now OnPacketProgress(). It
doesn't always send ACK, only when the host expects it.

+
+  VideoStub* video_stub_;
   ProtobufMessageParser<VideoPacket> parser_;
 
   DISALLOW_COPY_AND_ASSIGN(ClientVideoDispatcher);