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

net/base/mapped_host_resolver.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_MAPPED_HOST_RESOLVER_H_
 #define NET_BASE_MAPPED_HOST_RESOLVER_H_
 
 #include <string>
 
 #include "base/memory/scoped_ptr.h"
 #include "net/base/host_mapping_rules.h"
 #include "net/base/host_resolver.h"
 #include "net/base/net_export.h"
 
 namespace net {
 
 // This class wraps an existing HostResolver instance, but modifies the
 // request before passing it off to |impl|. This is different from
 // MockHostResolver which does the remapping at the HostResolverProc
 // layer, so it is able to preserve the effectiveness of the cache.
 class NET_EXPORT MappedHostResolver : public HostResolver {
  public:
   // Creates a MappedHostResolver that forwards all of its requests through
-  // |impl|.  It takes ownership of |impl|.
-  explicit MappedHostResolver(HostResolver* impl);
+  // |impl|.
+  explicit MappedHostResolver(scoped_ptr<HostResolver> impl);
   virtual ~MappedHostResolver();
 
   // Adds a rule to this mapper. The format of the rule can be one of:
   //
   //   "MAP" <hostname_pattern> <replacement_host> [":" <replacement_port>]
   //   "EXCLUDE" <hostname_pattern>
   //
   // The <replacement_host> can be either a hostname, or an IP address literal.
   //
   // Returns true if the rule was successfully parsed and added.
@@ skipping 24 matching lines @@
   RequestInfo ApplyRules(const RequestInfo& info) const;
 
   scoped_ptr<HostResolver> impl_;
 
   HostMappingRules rules_;
 };
 
 }  // namespace net
 
 #endif  // NET_BASE_MAPPED_HOST_RESOLVER_H_