Revert of Remove obsolete QUIC disabling code.

net/http/http_stream_factory_impl_job_controller.cc

Index: net/http/http_stream_factory_impl_job_controller.cc
diff --git a/net/http/http_stream_factory_impl_job_controller.cc b/net/http/http_stream_factory_impl_job_controller.cc
index d9c4b6e774c593d67ccac6d889b20b5dec3dca96..0083cc433832a126fd423fae0f82e14f04297ec6 100644
--- a/net/http/http_stream_factory_impl_job_controller.cc
+++ b/net/http/http_stream_factory_impl_job_controller.cc
@@ -908,7 +908,8 @@
       continue;
     }
 
-    if (session_->quic_stream_factory()->IsQuicDisabled())
+    if (session_->quic_stream_factory()->IsQuicDisabled(
+            alternative_service.port))
       continue;
 
     if (!original_url.SchemeIs("https"))
@@ -996,9 +997,11 @@
   }
 
   if (alternative_proxy_server->is_quic()) {
-    // Check that QUIC is enabled globally, and it is not disabled.
+    // Check that QUIC is enabled globally, and it is not disabled on
+    // the specified port.
     if (!session_->params().enable_quic ||
-        session_->quic_stream_factory()->IsQuicDisabled()) {
+        session_->quic_stream_factory()->IsQuicDisabled(
+            alternative_proxy_server->host_port_pair().port())) {
       return false;
     }
   }