Simplify message parsing.

remoting/protocol/channel_dispatcher_base.cc

Index: remoting/protocol/channel_dispatcher_base.cc
diff --git a/remoting/protocol/channel_dispatcher_base.cc b/remoting/protocol/channel_dispatcher_base.cc
index cd0823b2835b467a4aed4bdff3ed4316d7c65d3b..36d60dde564fe4d65cc19ccb77e1d8bd46c0b1c0 100644
--- a/remoting/protocol/channel_dispatcher_base.cc
+++ b/remoting/protocol/channel_dispatcher_base.cc
@@ -47,12 +47,21 @@ void ChannelDispatcherBase::OnChannelReady(
       base::Bind(&ChannelDispatcherBase::OnReadWriteFailed,
                  base::Unretained(this)));
   reader_.StartReading(channel_.get(),
+                       base::Bind(&ChannelDispatcherBase::OnIncomingMessage,
+                                  base::Unretained(this)),
                        base::Bind(&ChannelDispatcherBase::OnReadWriteFailed,
                                   base::Unretained(this)));
 
   event_handler_->OnChannelInitialized(this);
 }
 
+void ChannelDispatcherBase::OnIncomingMessage(
+    scoped_ptr<CompoundBuffer> message) {
+  // By default incoming message are not expected. Child classes override
+  // OnIncomingMessage() if the want to handle incoming messages.
+  LOG(ERROR) << "Received unexpected message on " << channel_name();
+}
+
 void ChannelDispatcherBase::OnReadWriteFailed(int error) {
   event_handler_->OnChannelError(this, CHANNEL_CONNECTION_ERROR);
 }