[Chromoting] Add plumbing to carry clipboard events from the host to the client.

remoting/protocol/client_control_dispatcher.cc

Index: remoting/protocol/client_control_dispatcher.cc
diff --git a/remoting/protocol/client_control_dispatcher.cc b/remoting/protocol/client_control_dispatcher.cc
index b1aefc2f3da0c6c2bcfaa249afedae16dae9c2d8..b6e8250d761319adfb89d3e4b6ba864c5f4242fe 100644
--- a/remoting/protocol/client_control_dispatcher.cc
+++ b/remoting/protocol/client_control_dispatcher.cc
@@ -21,6 +21,7 @@ namespace protocol {
 ClientControlDispatcher::ClientControlDispatcher()
     : ChannelDispatcherBase(kControlChannelName),
       client_stub_(NULL),
+      clipboard_stub_(NULL),
       writer_(new BufferedSocketWriter(base::MessageLoopProxy::current())) {
 }
 
@@ -45,8 +46,14 @@ void ClientControlDispatcher::InjectClipboardEvent(
 void ClientControlDispatcher::OnMessageReceived(
     scoped_ptr<ControlMessage> message, const base::Closure& done_task) {
   DCHECK(client_stub_);
+  DCHECK(clipboard_stub_);
   base::ScopedClosureRunner done_runner(done_task);
-  LOG(WARNING) << "Unknown control message received.";
+
+  if (message->has_clipboard_event()) {
+    clipboard_stub_->InjectClipboardEvent(message->clipboard_event());
+  } else {
+    LOG(WARNING) << "Unknown control message received.";
+  }
 }
 
 }  // namespace protocol