DNS: Support reprioritization of requests.

net/dns/host_resolver_impl.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_DNS_HOST_RESOLVER_IMPL_H_
 #define NET_DNS_HOST_RESOLVER_IMPL_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 122 matching lines @@
   // HostResolver methods:
   int Resolve(const RequestInfo& info,
               RequestPriority priority,
               AddressList* addresses,
               const CompletionCallback& callback,
               RequestHandle* out_req,
               const BoundNetLog& source_net_log) override;
   int ResolveFromCache(const RequestInfo& info,
                        AddressList* addresses,
                        const BoundNetLog& source_net_log) override;
+  void ChangeRequestPriority(RequestHandle req,
+                             RequestPriority priority) override;
   void CancelRequest(RequestHandle req) override;
   void SetDnsClientEnabled(bool enabled) override;
   HostCache* GetHostCache() override;
   std::unique_ptr<base::Value> GetDnsConfigAsValue() const override;
 
   void set_proc_params_for_test(const ProcTaskParams& proc_params) {
     proc_params_ = proc_params;
   }
 
  private:
@@ skipping 171 matching lines @@
 // This function is only exposed so it can be unit-tested.
 // TODO(tfarina): It would be better to change the tests so this function
 // gets exercised indirectly through HostResolverImpl.
 NET_EXPORT_PRIVATE bool ResolveLocalHostname(base::StringPiece host,
                                              uint16_t port,
                                              AddressList* address_list);
 
 }  // namespace net
 
 #endif  // NET_DNS_HOST_RESOLVER_IMPL_H_