Change the lifetime of the WebKit thread to be a subset of the IO thread's li...

chrome/browser/renderer_host/resource_dispatcher_host.h

Index: chrome/browser/renderer_host/resource_dispatcher_host.h
===================================================================
--- chrome/browser/renderer_host/resource_dispatcher_host.h	(revision 20100)
+++ chrome/browser/renderer_host/resource_dispatcher_host.h	(working copy)
@@ -292,7 +292,7 @@
   }
 
   WebKitThread* webkit_thread() const {
-    return webkit_thread_;
+    return webkit_thread_.get();
   }
 
   MessageLoop* ui_loop() const { return ui_loop_; }
@@ -529,7 +529,8 @@
 
   scoped_refptr<SafeBrowsingService> safe_browsing_;
 
-  scoped_refptr<WebKitThread> webkit_thread_;
+  // We own the WebKit thread and see to its destruction.
+  scoped_ptr<WebKitThread> webkit_thread_;
 
   // Request ID for browser initiated requests. request_ids generated by
   // child processes are counted up from 0, while browser created requests