Revert 143251 - Log stack trace when ObjectWatcher::StartWatching() is called.

base/win/object_watcher.h

Index: base/win/object_watcher.h
===================================================================
--- base/win/object_watcher.h	(revision 143465)
+++ base/win/object_watcher.h	(working copy)
@@ -1,4 +1,4 @@
-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -10,7 +10,6 @@
 
 #include "base/base_export.h"
 #include "base/callback.h"
-#include "base/debug/stack_trace.h"
 #include "base/memory/weak_ptr.h"
 #include "base/message_loop.h"
 
@@ -94,9 +93,6 @@
   HANDLE wait_object_;        // Returned by RegisterWaitForSingleObject
   MessageLoop* origin_loop_;  // Used to get back to the origin thread
 
-  // For debugging crbug.com/121086.
-  base::debug::StackTrace stack_trace_;
-
   DISALLOW_COPY_AND_ASSIGN(ObjectWatcher);
 };