PPAPI: Never re-enter JavaScript for PostMessage.

content/renderer/pepper/host_dispatcher_wrapper.cc

 // 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.
 
 #include "content/renderer/pepper/host_dispatcher_wrapper.h"
 
 #include "content/common/view_messages.h"
 #include "content/renderer/pepper/pepper_hung_plugin_filter.h"
 #include "content/renderer/pepper/pepper_plugin_instance_impl.h"
 #include "content/renderer/pepper/pepper_proxy_channel_delegate_impl.h"
@@ skipping 14 matching lines @@
       peer_pid_(peer_pid),
       plugin_child_id_(plugin_child_id),
       permissions_(perms),
       is_external_(is_external) {}
 
 HostDispatcherWrapper::~HostDispatcherWrapper() {}
 
 bool HostDispatcherWrapper::Init(const IPC::ChannelHandle& channel_handle,
                                  PP_GetInterface_Func local_get_interface,
                                  const ppapi::Preferences& preferences,
-                                 PepperHungPluginFilter* filter) {
+                                 scoped_refptr<PepperHungPluginFilter> filter) {
   if (channel_handle.name.empty())
     return false;
 
 #if defined(OS_POSIX)
   DCHECK_NE(-1, channel_handle.socket.fd);
   if (channel_handle.socket.fd == -1)
     return false;
 #endif
 
   dispatcher_delegate_.reset(new PepperProxyChannelDelegateImpl);
   dispatcher_.reset(new ppapi::proxy::HostDispatcher(
-      module_->pp_module(), local_get_interface, filter, permissions_));
+      module_->pp_module(), local_get_interface, permissions_));
+  // The HungPluginFilter needs to know when we are blocked on a sync message
+  // to the plugin. Note the filter outlives the dispatcher, so there is no
+  // need to remove it as an observer.
+  dispatcher_->AddSyncMessageStatusObserver(filter.get());
+  // Guarantee the hung_plugin_filter_ outlives |dispatcher_|.
+  hung_plugin_filter_ = filter;
 
   if (!dispatcher_->InitHostWithChannel(dispatcher_delegate_.get(),
                                         peer_pid_,
                                         channel_handle,
                                         true,  // Client.
                                         preferences)) {
     dispatcher_.reset();
     dispatcher_delegate_.reset();
     return false;
   }
+  // HungPluginFilter needs to listen for some messages on the IO thread.
+  dispatcher_->AddIOThreadMessageFilter(filter);
+
   dispatcher_->channel()->SetRestrictDispatchChannelGroup(
       kRendererRestrictDispatchGroup_Pepper);
   return true;
 }
 
 const void* HostDispatcherWrapper::GetProxiedInterface(const char* name) {
   return dispatcher_->GetProxiedInterface(name);
 }
 
 void HostDispatcherWrapper::AddInstance(PP_Instance instance) {
@@ skipping 29 matching lines @@
   if (host) {
     RenderFrame* render_frame = host->GetRenderFrameForInstance(instance);
     if (render_frame) {
       render_frame->Send(new ViewHostMsg_DidDeleteOutOfProcessPepperInstance(
           plugin_child_id_, instance, is_external_));
     }
   }
 }
 
 }  // namespace content