iwyu: Include stringprintf.h where appropriate, part 1.

net/http/http_util.cc

 // 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.
 
 // The rules for parsing content-types were borrowed from Firefox:
 // http://lxr.mozilla.org/mozilla/source/netwerk/base/src/nsURLHelper.cpp#834
 
 #include "net/http/http_util.h"
 
 #include <algorithm>
 
 #include "base/basictypes.h"
 #include "base/logging.h"
+#include "base/stringprintf.h"
 #include "base/string_number_conversions.h"
 #include "base/string_piece.h"
 #include "base/string_util.h"
 
 using std::string;
 
 namespace net {
 
 //-----------------------------------------------------------------------------
 
@@ skipping 761 matching lines @@
       value_is_quoted_ = true;
       // Do not store iterators into this. See declaration of unquoted_value_.
       unquoted_value_ = HttpUtil::Unquote(value_begin_, value_end_);
     }
   }
 
   return true;
 }
 
 }  // namespace net