Add support to ProxyService for downloading a PAC script on behalf of the Pro...

net/proxy/proxy_resolver_mac.h

 // Copyright (c) 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.
 
 #ifndef NET_PROXY_PROXY_RESOLVER_MAC_H_
 #define NET_PROXY_PROXY_RESOLVER_MAC_H_
 
 #include "net/proxy/proxy_service.h"
 
 namespace net {
 
 // Implementation of ProxyResolver that uses the Mac CFProxySupport to implement
 // proxies.
 class ProxyResolverMac : public ProxyResolver {
  public:
+  ProxyResolverMac() : ProxyResolver(true) {}
+
   // ProxyResolver methods:
   virtual int GetProxyForURL(const GURL& query_url,
                              const GURL& pac_url,
                              ProxyInfo* results);
 };
 
 class ProxyConfigServiceMac : public ProxyConfigService {
  public:
   // ProxyConfigService methods:
   virtual int GetProxyConfig(ProxyConfig* config);
 };
 
 }  // namespace net
 
 #endif  // NET_PROXY_PROXY_RESOLVER_MAC_H_