PPAPI: Refactor MessageChannel to prep for sync postMessae

content/renderer/pepper/renderer_ppapi_host_impl.h

Index: content/renderer/pepper/renderer_ppapi_host_impl.h
diff --git a/content/renderer/pepper/renderer_ppapi_host_impl.h b/content/renderer/pepper/renderer_ppapi_host_impl.h
index 8da1411942ed536a4a6ae7af79e1098e912cbfb7..a30735dc3c4f359b902d9c242dfca4f939086563 100644
--- a/content/renderer/pepper/renderer_ppapi_host_impl.h
+++ b/content/renderer/pepper/renderer_ppapi_host_impl.h
@@ -73,6 +73,8 @@ class RendererPpapiHostImpl : public RendererPpapiHost {
 
   PepperPluginInstanceImpl* GetPluginInstanceImpl(PP_Instance instance) const;
 
+  bool IsExternalPluginHost() const;
+
   // RendererPpapiHost implementation.
   virtual ppapi::host::PpapiHost* GetPpapiHost() OVERRIDE;
   virtual bool IsValidInstance(PP_Instance instance) const OVERRIDE;
@@ -94,6 +96,8 @@ class RendererPpapiHostImpl : public RendererPpapiHost {
       base::PlatformFile handle,
       bool should_close_source) OVERRIDE;
   virtual bool IsRunningInProcess() const OVERRIDE;
+  virtual std::string GetPluginName() const OVERRIDE;
+  virtual void SetToExternalPluginHost() OVERRIDE;
   virtual void CreateBrowserResourceHosts(
       PP_Instance instance,
       const std::vector<IPC::Message>& nested_msgs,
@@ -130,6 +134,9 @@ class RendererPpapiHostImpl : public RendererPpapiHost {
   // Whether the plugin is running in process.
   bool is_running_in_process_;
 
+  // Whether this is a host for external plugins.
+  bool is_external_plugin_host_;
+
   DISALLOW_COPY_AND_ASSIGN(RendererPpapiHostImpl);
 };