PPAPI: Support sending browser-hosted resources synchronously

content/renderer/pepper/message_channel.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_RENDERER_PEPPER_MESSAGE_CHANNEL_H_
 #define CONTENT_RENDERER_PEPPER_MESSAGE_CHANNEL_H_
 
 #include <deque>
 #include <list>
 #include <map>
@@ skipping 168 matching lines @@
   MessageQueueState plugin_message_queue_state_;
 
   std::map<std::string, ppapi::ScopedPPVar> internal_named_properties_;
 
   V8VarConverter var_converter_;
 
   // A callback to invoke at shutdown to ensure we unregister ourselves as
   // Observers for sync messages.
   base::Closure unregister_observer_callback_;
 
+  // This one is used only for var conversion result callbacks. In some cases,
+  // we want to force pending conversions to happen synchronously and cancel
+  // all pending callbacks.
+  base::WeakPtrFactory<MessageChannel> var_conversion_weak_ptr_factory_;
+
   // This is used to ensure pending tasks will not fire after this object is
   // destroyed.
   base::WeakPtrFactory<MessageChannel> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(MessageChannel);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_PEPPER_MESSAGE_CHANNEL_H_