Make sure that the UI window created by base::MessagePumpForUI is destoyed on the same thread (Wind…

base/message_pump.h

 // 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.
 
 #ifndef BASE_MESSAGE_PUMP_H_
 #define BASE_MESSAGE_PUMP_H_
 
 #include "base/base_export.h"
 #include "base/memory/ref_counted.h"
 
@@ skipping 101 matching lines @@
   // DoWork callback is already scheduled.  This method may be called from any
   // thread.  Once this call is made, DoWork should not be "starved" at least
   // until it returns a value of false.
   virtual void ScheduleWork() = 0;
 
   // Schedule a DoDelayedWork callback to happen at the specified time,
   // cancelling any pending DoDelayedWork callback.  This method may only be
   // used on the thread that called Run.
   virtual void ScheduleDelayedWork(const TimeTicks& delayed_work_time) = 0;
 
+  // Stops the pump and frees any resources that must to be freed on the thread
+  // that called Run(). The method should be called on the same thread that
+  // called Run().
+  //
+  // Note that this method is the last chance to run anything on the thread that
+  // called Run(). MessagePump is a ref-counted class. Its destructor can (and
+  // does) run on arbitraty thread.

[darin (slow to review), 2013/06/18 20:31:16]

nit: s/arbitraty/arbitrary/

This comment section seems to re-state the same thing a few times.  I bet you
could tighten it up a bit.

[alexeypa (please no reviews), 2013/06/18 20:48:52]

Done.

+  virtual void Shutdown() = 0;
+
  protected:
   virtual ~MessagePump();
   friend class RefCountedThreadSafe<MessagePump>;
 };
 
 }  // namespace base
 
 #endif  // BASE_MESSAGE_PUMP_H_