Allow renderer to create pepper ResourceHosts in the browser

ppapi/host/ppapi_host.h

Index: ppapi/host/ppapi_host.h
diff --git a/ppapi/host/ppapi_host.h b/ppapi/host/ppapi_host.h
index c661a9be59177d4192d76361ce3e9a0d60b032be..0b3d23ddbc59ceed565074377496a87e12148ac4 100644
--- a/ppapi/host/ppapi_host.h
+++ b/ppapi/host/ppapi_host.h
@@ -61,6 +61,12 @@ class PPAPI_HOST_EXPORT PpapiHost : public IPC::Sender, public IPC::Listener {
   // Sends the given unsolicited reply message to the plugin.
   void SendUnsolicitedReply(PP_Resource resource, const IPC::Message& msg);
 
+  // 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.