Add Alternative Service field trial.

Before this CL:
 * If "use_alternative_service" QUIC trial param was set, both same host and
   different host Alt-Svc headers were parsed and used.  If this param was not
   set, no Alt-Svc headers were parsed, and in-memory entries (from
   Alternate-protocol headers or loaded from disk) were only used if they
   referred to the same host.

After this CL:
 * AltSvc field trial controls whether Alt-Svc headers are parsed.
 * "enable_alternative_service_with_different_host" QUIC trial param control
   whether in-memory Alt-Svc entries with different host (parsed in current
   session or loaded from disk) are used.

Default values are not changed by this CL.

This CL allows testing of same-host Alt-Svc header behavior.  If no issues are
encountered, parsing Alt-Svc headers and using same-host entries can be enabled
by default, and Alternate-Protocols removed.

BUG=581331

Review URL: https://codereview.chromium.org/1639913002

Cr-Commit-Position: refs/heads/master@{#372348}

1 files changed, 4 insertions, 2 deletions

diff --git a/jingle/glue/proxy_resolving_client_socket.cc b/jingle/glue/proxy_resolving_client_socket.cc
index ae256144..e54ca93 100644
--- a/jingle/glue/proxy_resolving_client_socket.cc
+++ b/jingle/glue/proxy_resolving_client_socket.cc
@@ -87,8 +87,10 @@ ProxyResolvingClientSocket::ProxyResolvingClientSocket(
     session_params.trusted_spdy_proxy = reference_params->trusted_spdy_proxy;
     session_params.forced_spdy_exclusions =
         reference_params->forced_spdy_exclusions;
-    session_params.use_alternative_services =
-        reference_params->use_alternative_services;
+    session_params.parse_alternative_services =
+        reference_params->parse_alternative_services;
+    session_params.enable_alternative_service_with_different_host =
+        reference_params->enable_alternative_service_with_different_host;
   }
 
   network_session_.reset(new net::HttpNetworkSession(session_params));