Reduce the amount of included header files. Vast change like in "Oh God! This...

net/http/http_cache.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.
 
 // This file declares a HttpTransactionFactory implementation that can be
 // layered on top of another HttpTransactionFactory to add HTTP caching.  The
 // caching logic follows RFC 2616 (any exceptions are called out in the code).
 //
 // The HttpCache takes a disk_cache::Backend as a parameter, and uses that for
 // the cache storage.
 //
 // See HttpTransactionFactory and HttpTransaction for more details.
 
 #ifndef NET_HTTP_HTTP_CACHE_H_
 #define NET_HTTP_HTTP_CACHE_H_
 
 #include <list>
-#include <string>
+#include <set>
 
 #include "base/basictypes.h"
 #include "base/hash_tables.h"
 #include "base/task.h"
 #include "net/http/http_transaction_factory.h"
 
 namespace disk_cache {
 class Backend;
 class Entry;
 }
@@ skipping 137 matching lines @@
 
   RevocableStore transactions_;
 
   DISALLOW_COPY_AND_ASSIGN(HttpCache);
 };
 
 }  // namespace net
 
 #endif  // NET_HTTP_HTTP_CACHE_H_