Make IPC::Channel::Listener:OnMessageReceived have a return value indicating ...

ipc/ipc_sync_channel.h

 // Copyright (c) 2010 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 IPC_IPC_SYNC_SENDER_H__
 #define IPC_IPC_SYNC_SENDER_H__
 #pragma once
 
 #include <string>
 #include <deque>
@@ skipping 88 matching lines @@
     }
 
    private:
     ~SyncContext();
     // ChannelProxy methods that we override.
 
     // Called on the listener thread.
     virtual void Clear();
 
     // Called on the IPC thread.
-    virtual void OnMessageReceived(const Message& msg);
+    virtual bool OnMessageReceived(const Message& msg);
     virtual void OnChannelError();
     virtual void OnChannelOpened();
     virtual void OnChannelClosed();
 
     // Cancels all pending Send calls.
     void CancelPendingSends();
 
     // WaitableEventWatcher::Delegate implementation.
     virtual void OnWaitableEventSignaled(base::WaitableEvent* arg);
 
@@ skipping 28 matching lines @@
 
   // Used to signal events between the IPC and listener threads.
   base::WaitableEventWatcher dispatch_watcher_;
 
   DISALLOW_COPY_AND_ASSIGN(SyncChannel);
 };
 
 }  // namespace IPC
 
 #endif  // IPC_IPC_SYNC_SENDER_H__