Fix a race condition in the Java Bridge when adding objects

content/browser/renderer_host/java/java_bridge_channel_host.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 CONTENT_BROWSER_RENDERER_HOST_JAVA_JAVA_BRIDGE_CHANNEL_HOST_H_
 #define CONTENT_BROWSER_RENDERER_HOST_JAVA_JAVA_BRIDGE_CHANNEL_HOST_H_
 #pragma once
 
 #include "content/common/np_channel_base.h"
 
 class JavaBridgeChannelHost : public NPChannelBase {
  public:
   static JavaBridgeChannelHost* GetJavaBridgeChannelHost(
-      int renderer_id, base::MessageLoopProxy*);
+      int renderer_id,
+      base::MessageLoopProxy* ipc_message_loop);
+
+  // A threadsafe function to generate a unique route ID. Used by the
+  // JavaBridgeDispatcherHost on the UI thread and this class on the WEBKIT
+  // thread.
+  static int ThreadsafeGenerateRouteID();
 
   // NPChannelBase implementation:
   virtual int GenerateRouteID() OVERRIDE;
 
   // NPChannelBase override:
   virtual bool Init(base::MessageLoopProxy* ipc_message_loop,
                     bool create_pipe_now,
                     base::WaitableEvent* shutdown_event) OVERRIDE;
   virtual bool Send(IPC::Message* msg) OVERRIDE;
 
  private:
   JavaBridgeChannelHost() {}
   friend class base::RefCountedThreadSafe<JavaBridgeChannelHost>;
   virtual ~JavaBridgeChannelHost() {}
 
   static NPChannelBase* ClassFactory() {
     return new JavaBridgeChannelHost();
   }
 
+  // Message handlers
+  void OnGenerateRouteID(int* route_id);
+
   DISALLOW_COPY_AND_ASSIGN(JavaBridgeChannelHost);
 };
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_JAVA_JAVA_BRIDGE_CHANNEL_HOST_H_