base: Remove non-const refs from the MRUCache implementation.

net/http/disk_based_cert_cache.h

 // Copyright (c) 2014 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_DISK_BASED_CERT_CACHE_H
 #define NET_HTTP_DISK_BASED_CERT_CACHE_H
 
 #include <string>
 
 #include "base/callback.h"
@@ skipping 45 matching lines @@
   // on SetCertificate and GetCertificate operations. Intended for test purposes
   // only.
   size_t mem_cache_misses_for_testing() const { return mem_cache_misses_; }
 
  private:
   class ReadWorker;
   class WriteWorker;
 
   // A functor used to free an OSCertHandle. Used by the MRUCertCache.
   struct CertFree {
-    void operator()(X509Certificate::OSCertHandle cert_handle);
+    void operator()(X509Certificate::OSCertHandle* cert_handle);
   };
 
   // An in-memory cache that is used to prevent redundantly reading
   // from disk.
   typedef base::MRUCacheBase<std::string,
                              X509Certificate::OSCertHandle,
                              CertFree> MRUCertCache;
 
   // ReadWorkerMap and WriteWorkerMap map cache keys to their
   // corresponding Workers.
@@ skipping 17 matching lines @@
   int mem_cache_hits_;
   int mem_cache_misses_;
 
   base::WeakPtrFactory<DiskBasedCertCache> weak_factory_;
   DISALLOW_COPY_AND_ASSIGN(DiskBasedCertCache);
 };
 
 }  // namespace net
 
 #endif  // NET_HTTP_DISK_BASED_CERT_CACHE_H