PPAPI: Add unlocking for PPP calls and callbacks. Add more locking.

ppapi/proxy/ppp_messaging_proxy.cc

 // Copyright (c) 2011 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.
 
 #include "ppapi/proxy/ppp_messaging_proxy.h"
 
 #include <algorithm>
 
 #include "ppapi/c/ppp_messaging.h"
 #include "ppapi/proxy/host_dispatcher.h"
 #include "ppapi/proxy/plugin_resource_tracker.h"
 #include "ppapi/proxy/plugin_var_tracker.h"
 #include "ppapi/proxy/ppapi_messages.h"
 #include "ppapi/proxy/serialized_var.h"
 #include "ppapi/shared_impl/ppapi_globals.h"
+#include "ppapi/shared_impl/proxy_lock.h"
 #include "ppapi/shared_impl/var_tracker.h"
 
 namespace ppapi {
 namespace proxy {
 
 namespace {
 
 void HandleMessage(PP_Instance instance, PP_Var message_data) {
   HostDispatcher* dispatcher = HostDispatcher::GetForInstance(instance);
   if (!dispatcher || (message_data.type == PP_VARTYPE_OBJECT)) {
@@ skipping 52 matching lines @@
   IPC_END_MESSAGE_MAP()
   return handled;
 }
 
 void PPP_Messaging_Proxy::OnMsgHandleMessage(
     PP_Instance instance, SerializedVarReceiveInput message_data) {
   PP_Var received_var(message_data.Get(dispatcher()));
   // SerializedVarReceiveInput will decrement the reference count, but we want
   // to give the recipient a reference.
   PpapiGlobals::Get()->GetVarTracker()->AddRefVar(received_var);
-  ppp_messaging_impl_->HandleMessage(instance, received_var);
+  CallWhileUnlocked(ppp_messaging_impl_->HandleMessage,
+                    instance,
+                    received_var);
 }
 
 }  // namespace proxy
 }  // namespace ppapi