FBTF: Remove "obviously" unneeded standard C++ library #includes.

chrome/browser/net/referrer.h

-// Copyright (c) 2006-2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2010 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.
 
 // This class helps to remember what domains may be needed to be resolved when a
 // navigation takes place to a given URL.  This information is gathered when a
 // navigation to a subresource identifies a referring URL.
 // When future navigations take place to known referrer sites, then we
 // speculatively either pre-warm a TCP/IP conneciton, or at a minimum, resolve
 // the host name via DNS.
 
 // All access to this class is performed via the Predictor class, which only
 // operates on the IO thread.
 
 #ifndef CHROME_BROWSER_NET_REFERRER_H_
 #define CHROME_BROWSER_NET_REFERRER_H_
 #pragma once
 
 #include <map>
-#include <string>
 
 #include "base/basictypes.h"
 #include "base/time.h"
 #include "googleurl/src/gurl.h"
 #include "net/base/host_port_pair.h"
 
 class Value;
 
 namespace chrome_browser_net {
 
@@ skipping 110 matching lines @@
 
   // We put these into a std::map<>, so we need copy constructors.
   // DISALLOW_COPY_AND_ASSIGN(Referrer);
   // TODO(jar): Consider optimization to use pointers to these instances, and
   // avoid deep copies during re-alloc of the containing map.
 };
 
 }  // namespace chrome_browser_net
 
 #endif  // CHROME_BROWSER_NET_REFERRER_H_