Revert r21117 as it caused reliability failures....

chrome/renderer/render_view.h

Index: chrome/renderer/render_view.h
===================================================================
--- chrome/renderer/render_view.h	(revision 21215)
+++ chrome/renderer/render_view.h	(working copy)
@@ -360,6 +360,12 @@
     delay_seconds_for_form_state_sync_ = delay_in_seconds;
   }
 
+  // Returns a message loop of type IO that can be used to run I/O jobs. The
+  // renderer thread is of type TYPE_DEFAULT, so doesn't support everything
+  // needed by some consumers. The returned thread will be the main thread of
+  // the renderer, which processes all IPC, to any I/O should be non-blocking.
+  MessageLoop* GetMessageLoopForIO();
+
   AudioMessageFilter* audio_message_filter() { return audio_message_filter_; }
 
   void OnClearFocusedNode();