Merge commit '50d3e596bbe89c95615f96eb71f6bc5be737a1db' into Basilisk-releasev2018.07.18

# Conflicts:
#	browser/app/profile/firefox.js
#	browser/components/preferences/jar.mn

1 files changed, 16 insertions, 1 deletions

diff --git a/dom/media/PeerConnection.js b/dom/media/PeerConnection.js
index 0c3021799..0569b15ae 100644
--- a/dom/media/PeerConnection.js
+++ b/dom/media/PeerConnection.js
@@ -516,6 +516,18 @@ RTCPeerConnection.prototype = {
     };
   },
 
+  // This implements the fairly common "Queue a task" logic
+  async _queueTaskWithClosedCheck(func) {
+    return new Promise(resolve => {
+      Services.tm.mainThread.dispatch({ run() {
+        if (!this._closed) {
+          func();
+          resolve();
+        }
+      }}, Ci.nsIThread.DISPATCH_NORMAL);
+    });
+  },
+
   /**
    * An RTCConfiguration may look like this:
    *
@@ -1445,7 +1457,10 @@ PeerConnectionObserver.prototype = {
         break;
 
       case "IceConnectionState":
-        this.handleIceConnectionStateChange(this._dompc._pc.iceConnectionState);
+        let connState = this._dompc._pc.iceConnectionState;
+        this._dompc._queueTaskWithClosedCheck(() => {
+          this.handleIceConnectionStateChange(connState);
+        });
         break;
 
       case "IceGatheringState":