Refactor channel dispatchers on the host side.

remoting/protocol/host_event_dispatcher.h

+// Copyright (c) 2011 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.
+
+#ifndef REMOTING_PROTOCOL_HOST_EVENT_DISPATCHER_H_
+#define REMOTING_PROTOCOL_HOST_EVENT_DISPATCHER_H_
+
+#include "base/basictypes.h"
+#include "remoting/protocol/message_reader.h"
+
+namespace remoting {
+namespace protocol {
+
+class EventMessage;
+class InputStub;
+class Session;
+
+// HostEventDispatcher dispatches incoming messages on the event
+// channel to InputStub.
+class HostEventDispatcher {
+ public:
+  typedef base::Callback<void(int64)> SequenceNumberCallback;
+
+  HostEventDispatcher();
+  virtual ~HostEventDispatcher();
+
+  // Initialize the event channel and the dispatcher for the
+  // |session|. Doesn't take ownership of |session|.

[Wez, 2011/11/17 22:25:16]

nit: Caller retains ...

[Sergey Ulanov, 2011/11/17 22:41:39]

Done.

+  void Init(Session* session);
+
+  // Set InputStub that will be called for each incoming input
+  // message. Doesn't take ownershipt of |input_stub|. It must outlive
+  // the dispatcher.

[Wez, 2011/11/17 22:25:16]

typo, and nit: Caller retains ...

[Sergey Ulanov, 2011/11/17 22:41:39]

Caller doesn't own input_stub, so i think "caller retains" would be incorrect.

+  void set_input_stub(InputStub* input_stub) { input_stub_ = input_stub; }
+
+  // Set callback that will be called with sequence number received in

[Wez, 2011/11/17 22:25:16]

nit: Set a callback to notify of each message's sequence number.

[Sergey Ulanov, 2011/11/17 22:41:39]

Done.

+  // each message.

[Wez, 2011/11/17 22:25:16]

Clarify that this callback is not permitted to tear anything down?

[Sergey Ulanov, 2011/11/17 22:41:39]

Done.

+  void set_sequence_number_callback(const SequenceNumberCallback& value) {
+    sequence_number_callback_ = value;
+  }
+
+ private:
+  // This method is called by |reader_| when a message is received.
+  void OnMessageReceived(EventMessage* message,
+                         const base::Closure& done_task);
+
+  InputStub* input_stub_;
+  SequenceNumberCallback sequence_number_callback_;
+
+  ProtobufMessageReader<EventMessage> reader_;
+
+  DISALLOW_COPY_AND_ASSIGN(HostEventDispatcher);
+};
+
+}  // namespace protocol
+}  // namespace remoting
+
+#endif  // REMOTING_PROTOCOL_HOST_EVENT_DISPATCHER_H_