Reverts a commit that caused ASAN failures, and 2 dependent commits.

net/url_request/view_cache_helper.h

 // 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.
 
 #ifndef NET_URL_REQUEST_VIEW_CACHE_HELPER_H_
 #define NET_URL_REQUEST_VIEW_CACHE_HELPER_H_
 #pragma once
 
 #include <string>
 
@@ skipping 96 matching lines @@
   int buf_len_;
   int index_;
 
   std::string key_;
   std::string url_prefix_;
   std::string* data_;
   CompletionCallback callback_;
 
   State next_state_;
 
-  CompletionCallback cache_callback_;
-  OldCompletionCallbackImpl<ViewCacheHelper> old_cache_callback_;
+  OldCompletionCallbackImpl<ViewCacheHelper> cache_callback_;
   scoped_refptr<CancelableOldCompletionCallback<ViewCacheHelper> > entry_callback_;
 
   DISALLOW_COPY_AND_ASSIGN(ViewCacheHelper);
 };
 
 }  // namespace net.
 
 #endif  // NET_URL_REQUEST_VIEW_CACHE_HELPER_H_