Create a transition API for the debug message handler

src/debug-agent.cc

 // Copyright 2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 88 matching lines @@
   if (session_ != NULL) {
     static const char* message = "Remote debugging session already active\r\n";
 
     client->Send(message, strlen(message));
     delete client;
     return;
   }
 
   // Create a new session and hook up the debug message handler.
   session_ = new DebuggerAgentSession(this, client);
-  v8::Debug::SetMessageHandler(DebuggerAgentMessageHandler);
+  v8::Debug::SetMessageHandler2(DebuggerAgentMessageHandler);
   session_->Start();
 }
 
 
 void DebuggerAgent::CloseSession() {
   ScopedLock with(session_access_);
 
   // Terminate the session.
   if (session_ != NULL) {
     session_->Shutdown();
@@ skipping 288 matching lines @@
       return total_received;
     }
     total_received += received;
   }
   return total_received;
 }
 
 } }  // namespace v8::internal
 
 #endif  // ENABLE_DEBUGGER_SUPPORT