[PPAPI] Implement an IOStreamResource for data transmission between plugin and renderer.

ppapi/host/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 PPAPI_HOST_PPAPI_HOST_H_
 #define PPAPI_HOST_PPAPI_HOST_H_
 
 #include <map>
 
 #include "base/compiler_specific.h"
 #include "base/memory/linked_ptr.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
 #include "base/observer_list.h"
 #include "ipc/ipc_listener.h"
 #include "ipc/ipc_sender.h"
 #include "ppapi/c/pp_instance.h"
 #include "ppapi/c/pp_resource.h"
 #include "ppapi/host/ppapi_host_export.h"
 #include "ppapi/shared_impl/ppapi_permissions.h"
 
 namespace ppapi {
 
 namespace proxy {
 class ResourceMessageCallParams;
 class ResourceMessageReplyParams;
+class SerializedHandle;
 }
 
 namespace host {
 
 class HostFactory;
 struct HostMessageContext;
 class InstanceMessageFilter;
 struct ReplyMessageContext;
 class ResourceHost;
 
@@ skipping 17 matching lines @@
   // Listener implementation.
   virtual bool OnMessageReceived(const IPC::Message& msg) OVERRIDE;
 
   // Sends the given reply message to the plugin.
   void SendReply(const ReplyMessageContext& context,
                  const IPC::Message& msg);
 
   // Sends the given unsolicited reply message to the plugin.
   void SendUnsolicitedReply(PP_Resource resource, const IPC::Message& msg);
 
+  // Similar to SendUnsolicitedReply, but it support send a file handler.

[bbudge, 2013/12/31 00:51:53]

s/support send/supports sending
s/file handler/file handle/

[Peng, 2013/12/31 23:33:54]

Done.

+  void SendUnsolicitedReplyWithHandle(
+      PP_Resource resource,
+      const IPC::Message& msg,
+      const ppapi::proxy::SerializedHandle& handle);
+
   // Create a ResourceHost with the given |nested_msg|.
   scoped_ptr<ResourceHost> CreateResourceHost(
       const proxy::ResourceMessageCallParams& params,
       PP_Instance instance,
       const IPC::Message& nested_msg);
 
   // Adds the given host resource as a pending one (with no corresponding
   // PluginResource object and no PP_Resource ID yet). The pending resource ID
   // is returned. See PpapiHostMsg_AttachToPendingHost.
   int AddPendingResourceHost(scoped_ptr<ResourceHost> resource_host);
@@ skipping 61 matching lines @@
   PendingHostResourceMap pending_resource_hosts_;
   int next_pending_resource_host_id_;
 
   DISALLOW_COPY_AND_ASSIGN(PpapiHost);
 };
 
 }  // namespace host
 }  // namespace ppapi
 
 #endif  // PPAPI_HOST_PPAPIE_HOST_H_