Created a MessageLoopProxy interface. This provides a thread-safe refcounted ...

chrome/browser/chrome_thread.h

Index: chrome/browser/chrome_thread.h
===================================================================
--- chrome/browser/chrome_thread.h	(revision 45861)
+++ chrome/browser/chrome_thread.h	(working copy)
@@ -9,6 +9,8 @@
 #include "base/task.h"
 #include "base/thread.h"
 
+class MessageLoopProxy;
+
 ///////////////////////////////////////////////////////////////////////////////
 // ChromeThread
 //
@@ -126,6 +128,11 @@
   // sets identifier to its ID.  Otherwise returns false.
   static bool GetCurrentThreadIdentifier(ID* identifier);
 
+  // Callers can hold on to a refcounted MessageLoopProxy beyond the lifetime
+  // of the thread.
+  static scoped_refptr<MessageLoopProxy> GetMessageLoopProxyForThread(
+      ID identifier);
+
   // Use these templates in conjuction with RefCountedThreadSafe when you want
   // to ensure that an object is deleted on a specific thread.  This is needed
   // when an object can hop between threads (i.e. IO -> FILE -> IO), and thread