[net] Change factory methods for HostResolver and HostCache to return a scoped_ptr

net/base/host_cache.h

 // Copyright (c) 2012 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_HOST_CACHE_H_
 #define NET_BASE_HOST_CACHE_H_
 
 #include <functional>
 #include <string>
 
 #include "base/gtest_prod_util.h"
+#include "base/memory/scoped_ptr.h"
 #include "base/threading/non_thread_safe.h"
 #include "base/time.h"
 #include "net/base/address_family.h"
 #include "net/base/address_list.h"
 #include "net/base/expiring_cache.h"
 #include "net/base/net_export.h"
 
 namespace net {
 
 // Cache used by HostResolver to map hostnames to their resolved result.
@@ skipping 58 matching lines @@
 
   // Returns the number of entries in the cache.
   size_t size() const;
 
   // Following are used by net_internals UI.
   size_t max_entries() const;
 
   const EntryMap& entries() const;
 
   // Creates a default cache.
-  static HostCache* CreateDefaultCache();
+  static scoped_ptr<HostCache> CreateDefaultCache();
 
  private:
   FRIEND_TEST_ALL_PREFIXES(HostCacheTest, NoCache);
 
   // Returns true if this HostCache can contain no entries.
   bool caching_is_disabled() const {
     return entries_.max_entries() == 0;
   }
 
   // Map from hostname (presumably in lowercase canonicalized format) to
   // a resolved result entry.
   EntryMap entries_;
 
   DISALLOW_COPY_AND_ASSIGN(HostCache);
 };
 
 }  // namespace net
 
 #endif  // NET_BASE_HOST_CACHE_H_