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

net/http/disk_cache_based_ssl_host_info.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_HTTP_DISK_CACHE_BASED_SSL_HOST_INFO_H_
 #define NET_HTTP_DISK_CACHE_BASED_SSL_HOST_INFO_H_
 
 #include <string>
 
 #include "base/memory/scoped_ptr.h"
@@ skipping 88 matching lines @@
   // DoWaitForDataReadyDone is the terminal state of the read operation.
   int DoWaitForDataReadyDone();
 
   // DoSetDone is the terminal state of the write operation.
   int DoSetDone();
 
   // IsCallbackPending returns true if we have a pending callback.
   bool IsCallbackPending() const;
 
   base::WeakPtrFactory<DiskCacheBasedSSLHostInfo> weak_ptr_factory_;
-  CompletionCallback callback_;
+  CallbackImpl* callback_;
   State state_;
   bool ready_;
   bool found_entry_;  // Controls the behavior of DoCreateOrOpen.
   std::string new_data_;
   const std::string hostname_;
   HttpCache* const http_cache_;
   disk_cache::Backend* backend_;
   disk_cache::Entry* entry_;
   CompletionCallback user_callback_;
   scoped_refptr<IOBuffer> read_buffer_;
   scoped_refptr<IOBuffer> write_buffer_;
   std::string data_;
 };
 
 }  // namespace net
 
 #endif  // NET_HTTP_DISK_CACHE_BASED_SSL_HOST_INFO_H_