Simplify message parsing.

remoting/protocol/host_control_dispatcher.cc

Index: remoting/protocol/host_control_dispatcher.cc
diff --git a/remoting/protocol/host_control_dispatcher.cc b/remoting/protocol/host_control_dispatcher.cc
index 2b067d74cdf2d171ed4e6e6afc4467838259673a..fb8aee94188bc111745ec09d893eef012fd2c32e 100644
--- a/remoting/protocol/host_control_dispatcher.cc
+++ b/remoting/protocol/host_control_dispatcher.cc
@@ -17,16 +17,8 @@ namespace remoting {
 namespace protocol {
 
 HostControlDispatcher::HostControlDispatcher()
-    : ChannelDispatcherBase(kControlChannelName),
-      clipboard_stub_(nullptr),
-      host_stub_(nullptr),
-      parser_(base::Bind(&HostControlDispatcher::OnMessageReceived,
-                         base::Unretained(this)),
-              reader()) {
-}
-
-HostControlDispatcher::~HostControlDispatcher() {
-}
+    : ChannelDispatcherBase(kControlChannelName) {}
+HostControlDispatcher::~HostControlDispatcher() {}
 
 void HostControlDispatcher::SetCapabilities(
     const Capabilities& capabilities) {
@@ -62,11 +54,16 @@ void HostControlDispatcher::SetCursorShape(
   writer()->Write(SerializeAndFrameMessage(message), base::Closure());
 }
 
-void HostControlDispatcher::OnMessageReceived(
-    scoped_ptr<ControlMessage> message) {
+void HostControlDispatcher::OnIncomingMessage(
+    scoped_ptr<CompoundBuffer> buffer) {
   DCHECK(clipboard_stub_);
   DCHECK(host_stub_);
 
+  scoped_ptr<ControlMessage> message =
+      ParseMessage<ControlMessage>(buffer.get());
+  if (!message)
+    return;
+
   if (message->has_clipboard_event()) {
     clipboard_stub_->InjectClipboardEvent(message->clipboard_event());
   } else if (message->has_client_resolution()) {