Add the capability to run multiple proxy PAC scripts in parallel....

net/base/host_resolver.h

 // Copyright (c) 2010 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_RESOLVER_H_
 #define NET_BASE_HOST_RESOLVER_H_
 
 #include <string>
 
 #include "base/ref_counted.h"
@@ skipping 159 matching lines @@
   // unspecified. For example, this could be used to restrict resolution
   // results to AF_INET by passing in ADDRESS_FAMILY_IPV4, or to
   // AF_INET6 by passing in ADDRESS_FAMILY_IPV6.
   virtual void SetDefaultAddressFamily(AddressFamily address_family) {}
 
   // Returns |this| cast to a HostResolverImpl*, or NULL if the subclass
   // is not compatible with HostResolverImpl. Used primarily to expose
   // additional functionality on the about:net-internals page.
   virtual HostResolverImpl* GetAsHostResolverImpl() { return NULL; }
 
+  // Does additional cleanup prior to destruction.
+  virtual void Shutdown() {}
+
  protected:
   friend class base::RefCounted<HostResolver>;
 
   HostResolver() { }
 
   // If any completion callbacks are pending when the resolver is destroyed,
   // the host resolutions are cancelled, and the completion callbacks will not
   // be called.
   virtual ~HostResolver() {}
 
@@ skipping 43 matching lines @@
 };
 
 // Creates a HostResolver implementation that queries the underlying system.
 // (Except if a unit-test has changed the global HostResolverProc using
 // ScopedHostResolverProc to intercept requests to the system).
 HostResolver* CreateSystemHostResolver();
 
 }  // namespace net
 
 #endif  // NET_BASE_HOST_RESOLVER_H_