Test was examining a variable without first acquiring a required Lock....

base/lock_impl_win.cc

 // Copyright (c) 2006-2008 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.
 
 #include "base/lock_impl.h"
 #include "base/logging.h"
 
 // NOTE: Although windows critical sections support recursive locks, we do not
 // allow this, and we will commonly fire a DCHECK() if a thread attempts to
 // acquire the lock a second time (while already holding it).
@@ skipping 48 matching lines @@
 #ifndef NDEBUG
   --recursion_count_shadow_;  // ONLY access while lock is still held.
   DCHECK(0 <= recursion_count_shadow_);
   owning_thread_id_ = 0;
 #endif  // NDEBUG
   ::LeaveCriticalSection(&os_lock_);
 }
 
 // In non-debug builds, this method is declared as an empty inline method.
 #ifndef NDEBUG
-void LockImpl::AssertAcquired() {
+void LockImpl::AssertAcquired() const {
   DCHECK(recursion_count_shadow_ > 0);
   DCHECK_EQ(owning_thread_id_, PlatformThread::CurrentId());
 }
 #endif