net: Cleanup class/struct forward declarations

net/base/sdch_dictionary.h

 // Copyright 2015 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_BASE_SDCH_DICTIONARY_H_
 #define NET_BASE_SDCH_DICTIONARY_H_
 
 #include <stddef.h>
 
 #include <memory>
 #include <set>
 #include <string>
 
 #include "base/memory/ref_counted.h"
 #include "base/time/time.h"
 #include "net/base/net_export.h"
 #include "net/base/sdch_problem_codes.h"
 #include "url/gurl.h"
 
-namespace base {
-class Clock;
-class Value;
-}
-
 namespace net {
 
 // Contains all information for an SDCH dictionary.  This class is intended
 // to be used with a RefCountedData<> wrappers.  These dictionaries
 // are vended by SdchManager; see sdch_manager.h for details.
 class NET_EXPORT_PRIVATE SdchDictionary {
  public:
   // Construct a vc-diff usable dictionary from the dictionary_text starting
   // at the given offset. The supplied client_hash should be used to
   // advertise the dictionary's availability relative to the suppplied URL.
@@ skipping 68 matching lines @@
   const std::string path_;
   const base::Time expiration_;  // Implied by max-age.
   const std::set<int> ports_;
 
   void operator=(const SdchDictionary&) = delete;
 };
 
 }  // namespace net
 
 #endif  // NET_BASE_SDCH_DICTIONARY_H_