Bug 1430213 - add toggle pref for RTCRtpReceiver RTP sources APIs;r=jib,smaug

MozReview-Commit-ID: 7vKUDDpjiP2

--HG--
extra : rebase_source : 53a7c6f43879d216c06a16626050f21344afe293

dom/media/tests/mochitest/head.js

@@ -389,6 +389,7 @@ function setupEnvironment() {
       ['media.peerconnection.ice.stun_client_maximum_transmits', 14],
       ['media.peerconnection.ice.trickle_grace_period', 30000],
       ['media.peerconnection.remoteTrackId.enabled', true],
+      ['media.peerconnection.rtpsourcesapi.enabled', true],
       ['media.navigator.permission.disabled', true],
       ['media.navigator.streams.fake', FAKE_ENABLED],
       ['media.getusermedia.screensharing.enabled', true],

dom/webidl/RTCRtpReceiver.webidl

@@ -12,7 +12,9 @@
 interface RTCRtpReceiver {
   readonly attribute MediaStreamTrack   track;
   Promise<RTCStatsReport>               getStats();
+  [Pref="media.peerconnection.rtpsourcesapi.enabled"]
   sequence<RTCRtpContributingSource>    getContributingSources();
+  [Pref="media.peerconnection.rtpsourcesapi.enabled"]
   sequence<RTCRtpSynchronizationSource> getSynchronizationSources();
 
   [ChromeOnly]

modules/libpref/init/all.js

@@ -502,6 +502,7 @@ pref("media.peerconnection.ice.trickle_grace_period", 5000);
 pref("media.peerconnection.ice.no_host", false);
 pref("media.peerconnection.ice.default_address_only", false);
 pref("media.peerconnection.ice.proxy_only", false);
+pref("media.peerconnection.rtpsourcesapi.enabled", true);
 
 // These values (aec, agc, and noise) are from media/webrtc/trunk/webrtc/common_types.h
 // kXxxUnchanged = 0, kXxxDefault = 1, and higher values are specific to each