Implement ChildThread::shutdown and clear members that have refs into blink

content/child/child_thread.cc

Index: content/child/child_thread.cc
diff --git a/content/child/child_thread.cc b/content/child/child_thread.cc
index 859d2b2643e4463151504f0e1990e00f4fa880b1..7919a5e81db0651a27acc0a7e3655f40cc8720dc 100644
--- a/content/child/child_thread.cc
+++ b/content/child/child_thread.cc
@@ -195,6 +195,12 @@ ChildThread::~ChildThread() {
   g_lazy_tls.Pointer()->Set(NULL);
 }
 
+void ChildThread::Shutdown() {
+  // Delete objects that hold references to blink so derived classes can
+  // safely shutdown blink in their Shutdown implementation.
+  file_system_dispatcher_.reset();
+}
+
 void ChildThread::OnChannelConnected(int32 peer_pid) {
   channel_connected_factory_.InvalidateWeakPtrs();
 }
@@ -276,7 +282,8 @@ bool ChildThread::OnMessageReceived(const IPC::Message& msg) {
     return true;
   if (socket_stream_dispatcher_->OnMessageReceived(msg))
     return true;
-  if (file_system_dispatcher_->OnMessageReceived(msg))
+  if (file_system_dispatcher_ &&

[jam, 2013/07/23 16:44:23]

are you sure this can be called after shutdown?

+      file_system_dispatcher_->OnMessageReceived(msg))
     return true;
   if (quota_dispatcher_->OnMessageReceived(msg))
     return true;