Added a net::BidirectionalStream to expose a bidirectional streaming interface

net/http/http_stream_factory_impl.h

Index: net/http/http_stream_factory_impl.h
diff --git a/net/http/http_stream_factory_impl.h b/net/http/http_stream_factory_impl.h
index 1ac451dd99ec14c616be8c752486376d50e8260f..261aeccc4da4175e94f5f57dc093017b85bdad44 100644
--- a/net/http/http_stream_factory_impl.h
+++ b/net/http/http_stream_factory_impl.h
@@ -48,6 +48,14 @@ class NET_EXPORT_PRIVATE HttpStreamFactoryImpl : public HttpStreamFactory {
       WebSocketHandshakeStreamBase::CreateHelper* create_helper,
       const BoundNetLog& net_log) override;
 
+  HttpStreamRequest* RequestBidirectionalStream(
+      const HttpRequestInfo& info,
+      RequestPriority priority,
+      const SSLConfig& server_ssl_config,
+      const SSLConfig& proxy_ssl_config,
+      HttpStreamRequest::Delegate* delegate,
+      const BoundNetLog& net_log) override;
+
   void PreconnectStreams(int num_streams,
                          const HttpRequestInfo& info,
                          const SSLConfig& server_ssl_config,