Revert cl 9528 to fix mac test_shell_tests

net/http/http_transaction.h

 // 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.
 
 #ifndef NET_HTTP_HTTP_TRANSACTION_H_
 #define NET_HTTP_HTTP_TRANSACTION_H_
 
 #include "net/base/completion_callback.h"
 #include "net/base/load_states.h"
 
 namespace net {
 
 class HttpRequestInfo;
 class HttpResponseInfo;
-class IOBuffer;
 
 // Represents a single HTTP transaction (i.e., a single request/response pair).
 // HTTP redirects are not followed and authentication challenges are not
 // answered.  Cookies are assumed to be managed by the caller.
 class HttpTransaction {
  public:
   // Stops any pending IO and destroys the transaction object.
   virtual ~HttpTransaction() {}
 
   // Starts the HTTP transaction (i.e., sends the HTTP request).
@@ skipping 56 matching lines @@
 
   // Returns the upload progress in bytes.  If there is no upload data,
   // zero will be returned.  This does not include the request headers.
   virtual uint64 GetUploadProgress() const = 0;
 };
 
 }  // namespace net
 
 #endif  // NET_HTTP_HTTP_TRANSACTION_H_