Replace a DCHECK with DCHECK_EQ.

base/cancellation_flag.cc

Index: base/cancellation_flag.cc
===================================================================
--- base/cancellation_flag.cc	(revision 52168)
+++ base/cancellation_flag.cc	(working copy)
@@ -1,4 +1,4 @@
-// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Copyright (c) 2010 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 +10,7 @@
 
 void CancellationFlag::Set() {
 #if !defined(NDEBUG)
-  DCHECK(set_on_ == PlatformThread::CurrentId());
+  DCHECK_EQ(set_on_, PlatformThread::CurrentId());
 #endif
   base::subtle::Release_Store(&flag_, 1);
 }