Update comments in socket_dispatcher.h.

content/renderer/p2p/socket_dispatcher.h

 // Copyright (c) 2012 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.
 
 // P2PSocketDispatcher is a per-renderer object that dispatchers all
 // P2P messages received from the browser and relays all P2P messages
 // sent to the browser. P2PSocketClient instances register themselves
 // with the dispatcher using RegisterClient() and UnregisterClient().
 //
 // Relationship of classes.
 //
 //       P2PSocketHost                     P2PSocketClient
 //            ^                                   ^
 //            |                                   |
 //            v                  IPC              v
 //  P2PSocketDispatcherHost  <--------->  P2PSocketDispatcher
 //
+// P2PSocketDispatcher receives and dispatches messages on the
+// renderer thread.
 
 #ifndef CONTENT_RENDERER_P2P_SOCKET_DISPATCHER_H_
 #define CONTENT_RENDERER_P2P_SOCKET_DISPATCHER_H_
 
 #include <vector>
 
 #include "base/callback_forward.h"
 #include "base/compiler_specific.h"
 #include "base/id_map.h"
 #include "base/observer_list_threadsafe.h"
@@ skipping 15 matching lines @@
 
 namespace webkit_glue {
 class NetworkListObserver;
 }  // webkit_glue
 
 namespace content {
 
 class P2PHostAddressRequest;
 class P2PSocketClient;
 
-// P2PSocketDispatcher works on the renderer thread. It dispatches all
-// messages on that thread, and all its methods must be called on the
-// same thread.
 class CONTENT_EXPORT P2PSocketDispatcher : public content::RenderViewObserver {
  public:
   explicit P2PSocketDispatcher(RenderViewImpl* render_view);
   virtual ~P2PSocketDispatcher();
 
   // Add a new network list observer. Each observer is called
   // immidiately after it is registered and then later whenever
-  // network configuration changes.
+  // network configuration changes. Can be called on any thread. The
+  // observer is always called on the thread it was added.
   void AddNetworkListObserver(
       webkit_glue::NetworkListObserver* network_list_observer);
 
-  // Removes network list observer.
+  // Removes network list observer. Must be called on the thread on
+  // which the observer was added.
   void RemoveNetworkListObserver(
       webkit_glue::NetworkListObserver* network_list_observer);
 
   // RenderViewObserver overrides.
   virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
 
  private:
   friend class P2PHostAddressRequest;
   friend class P2PSocketClient;
   class AsyncMessageSender;
@@ skipping 31 matching lines @@
       network_list_observers_;
 
   scoped_refptr<AsyncMessageSender> async_message_sender_;
 
   DISALLOW_COPY_AND_ASSIGN(P2PSocketDispatcher);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_P2P_SOCKET_DISPATCHER_H_