PPAPI: Refactor MessageChannel to prep for sync postMessae

content/public/renderer/renderer_ppapi_host.h

 // Copyright (c) 2012 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_PUBLIC_RENDERER_RENDERER_PPAPI_HOST_H_
 #define CONTENT_PUBLIC_RENDERER_RENDERER_PPAPI_HOST_H_
 
 #include <vector>
 
 #include "base/callback_forward.h"
@@ skipping 105 matching lines @@
   // message fails, the returned handle is properly closed by the IPC system. If
   // |should_close_source| is set to true, the original handle is closed by this
   // operation and should not be used again.
   virtual IPC::PlatformFileForTransit ShareHandleWithRemote(
       base::PlatformFile handle,
       bool should_close_source) = 0;
 
   // Returns true if the plugin is running in process.
   virtual bool IsRunningInProcess() const = 0;
 
+  virtual std::string GetPluginName() const = 0;
+
+  // Used by the embedder to inform this RendererPpapiHost that the associated
+  // plugin module is a host for "external plugins."
+  //
+  // An embedder may, at the time a plugin module is created, configure it to
+  // be a host for external plugins. Instances of such plugins go through two
+  // two stages of initialization; the first stage initializes a host plugin
+  // instance, which then loads and initializes a child plugin which takes
+  // over control. These are treated as one Pepper Instance, because despite the
+  // two-stage initialization process, the host and child appear to blink as
+  // one plugin instance.
+  //
+  // The host plugin appears as an in-process plugin, while we interact with the
+  // child plugin via the Pepper proxy.
+  virtual void SetToExternalPluginHost() = 0;
+
   // There are times when the renderer needs to create a ResourceHost in the
   // browser. This function does so asynchronously. |nested_msgs| is a list of
   // resource host creation messages and |instance| is the PP_Instance which
   // the resource will belong to. |callback| will be called asynchronously with
   // the pending host IDs when the ResourceHosts have been created. This can be
   // passed back to the plugin to attach to the ResourceHosts. Pending IDs of 0
   // will be passed to the callback if a ResourceHost fails to be created.
   virtual void CreateBrowserResourceHosts(
       PP_Instance instance,
       const std::vector<IPC::Message>& nested_msgs,
       const base::Callback<void(const std::vector<int>&)>& callback) const = 0;
 
   // Gets the URL of the document containing the given PP_Instance.
   // Returns an empty URL if the instance is invalid.
   // TODO(yzshen): Some methods such as this one don't need to be pure virtual.
   // Instead, they could be directly implemented using other methods in this
   // interface. Consider changing them to static helpers.
   virtual GURL GetDocumentURL(PP_Instance instance) const = 0;
 
  protected:
   virtual ~RendererPpapiHost() {}
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_RENDERER_RENDERER_PPAPI_HOST_H_