Adding IceConfig option to assume TURN/TURN candidate pairs will work.

This will allow media to be sent on these pairs before a binding
response is received, shortening call setup time. However, this is only
possible if the TURN servers don't require CreatePermission when
communicating with each other.

R=honghaiz@webrtc.org, pthatcher@webrtc.org
NOTRY=True

Review-Url: https://codereview.webrtc.org/2063823008
Cr-Commit-Position: refs/heads/master@{#13268}
diff --git a/webrtc/api/webrtcsession_unittest.cc b/webrtc/api/webrtcsession_unittest.cc
index e8234d7..fab5e1a 100644
--- a/webrtc/api/webrtcsession_unittest.cc
+++ b/webrtc/api/webrtcsession_unittest.cc
@@ -2247,7 +2247,7 @@
   candidates = local_desc->candidates(kMediaContentIndex0);
   size_t num_local_candidates = candidates->count();
   // Enable Continual Gathering
-  session_->SetIceConfig(cricket::IceConfig(-1, -1, true, false, -1));
+  session_->SetIceConfig(cricket::IceConfig(-1, -1, true, false, -1, true));
   // Bring down the network interface to trigger candidate removals.
   RemoveInterface(rtc::SocketAddress(kClientAddrHost1, kClientAddrPort));
   // Verify that all local candidates are removed.