JobController: do not create alternative job for those AlternativeServiceInfo

net/http/http_stream_factory_impl_job_controller.h

 // Copyright (c) 2016 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_HTTP_HTTP_STREAM_FACTORY_IMPL_JOB_CONTROLLER_H_
 #define NET_HTTP_HTTP_STREAM_FACTORY_IMPL_JOB_CONTROLLER_H_
 
 #include <memory>
 
 #include "net/base/host_port_pair.h"
@@ skipping 247 matching lines @@
   AlternativeServiceInfo GetAlternativeServiceInfoFor(
       const HttpRequestInfo& request_info,
       HttpStreamRequest::Delegate* delegate,
       HttpStreamRequest::StreamType stream_type);
 
   AlternativeServiceInfo GetAlternativeServiceInfoInternal(
       const HttpRequestInfo& request_info,
       HttpStreamRequest::Delegate* delegate,
       HttpStreamRequest::StreamType stream_type);
 
+  // Returns a QuicVersion that has been advertised in |advertised_versions|
+  // and supported by the net stack.  If more than one QuicVersions are

[Ryan Hamilton, 2017/06/30 02:45:11]

nit: can you remove "by the net stack" from this comment (and elsewhere).

... " and is supported."

[Zhongyi Shi, 2017/06/30 21:08:43]

Done.

+  // supported, the first matched in the supported versions will be returned.
+  // If no mutually supported version is found,
+  // QUIC_VERSION_UNSUPPORTED_VERSION will be returned.
+  QuicVersion SelectQuicVersion(const QuicVersionVector& advertised_versions);
+
   // Remove session from the SpdySessionRequestMap.
   void RemoveRequestFromSpdySessionRequestMap();
 
   // Returns true if the |request_| can be fetched via an alternative
   // proxy server, and sets |alternative_proxy_server| to the available
   // alternative proxy server. |alternative_proxy_server| should not be null,
   // and is owned by the caller.
   bool ShouldCreateAlternativeProxyServerJob(
       const ProxyInfo& proxy_info_,
       const GURL& url,
@@ skipping 79 matching lines @@
   HttpStreamRequest::StreamType stream_type_;
   RequestPriority priority_;
   const NetLogWithSource net_log_;
 
   base::WeakPtrFactory<JobController> ptr_factory_;
 };
 
 }  // namespace net
 
 #endif  // NET_HTTP_HTTP_STREAM_FACTORY_IMPL_JOB_CONTROLLER_H_