Fix some issues found looking at the code. I have made two posts about it:...

base/base_drag_source.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 <atlbase.h>
 
 #include "base/base_drag_source.h"
 
 ///////////////////////////////////////////////////////////////////////////////
 // BaseDragSource, public:
@@ skipping 37 matching lines @@
   AddRef();
   return S_OK;
 }
 
 ULONG BaseDragSource::AddRef() {
   return InterlockedIncrement(&ref_count_);
 }
 
 ULONG BaseDragSource::Release() {
   if (InterlockedDecrement(&ref_count_) == 0) {
-    ULONG copied_refcnt = ref_count_;
     delete this;
-    return copied_refcnt;
+    return 0U;
   }
   return ref_count_;
 }