Fix a race condition in the Java Bridge when adding objects

content/browser/renderer_host/java/java_bridge_channel_host.h

Index: content/browser/renderer_host/java/java_bridge_channel_host.h
diff --git a/content/browser/renderer_host/java/java_bridge_channel_host.h b/content/browser/renderer_host/java/java_bridge_channel_host.h
index 424d42eec6fbc6013d40cb97392cc6a6bec610c6..f8948464b2ee7eaa5a78763738c5646f38d577f5 100644
--- a/content/browser/renderer_host/java/java_bridge_channel_host.h
+++ b/content/browser/renderer_host/java/java_bridge_channel_host.h
@@ -11,7 +11,13 @@
 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;
@@ -31,6 +37,9 @@ class JavaBridgeChannelHost : public NPChannelBase {
     return new JavaBridgeChannelHost();
   }
 
+  // Message handlers
+  void OnGenerateRouteID(int* route_id);
+
   DISALLOW_COPY_AND_ASSIGN(JavaBridgeChannelHost);
 };