Bug 1359849 - Guard against exceptions thrown while cleaning up the video controls. r=gijs

MozReview-Commit-ID: 2cwIE7Xdp7O

toolkit/content/widgets/videocontrols.xml

@@ -715,17 +715,21 @@
       terminateEventListeners() {
         if (this.videoEvents) {
           for (let event of this.videoEvents) {
+            try {
               this.video.removeEventListener(event, this, {
                 capture: true,
                 mozSystemGroup: true
               });
+            } catch (ex) {}
           }
         }
 
         if (this.controlListeners) {
           for (let element of this.controlListeners) {
+            try {
               element.item.removeEventListener(element.event, element.func,
                 { mozSystemGroup: true, capture: element.capture });
+            } catch (ex) {}
           }
 
           delete this.controlListeners;
@@ -2041,7 +2045,9 @@
       handleEvent(aEvent) {
         if (aEvent.type == "transitionend") {
           this.firstShow = false;
+          try {
             this.videocontrols.removeEventListener("transitionend", this);
+          } catch (ex) {}
           return;
         }
 
@@ -2052,7 +2058,9 @@
 
       terminateEventListeners() {
         for (var event of this.videoEvents) {
+          try {
             this.Utils.video.removeEventListener(event, this);
+          } catch (ex) {}
         }
       },
 
@@ -2197,12 +2205,16 @@
       controlListeners: [],
       terminateEventListeners() {
         for (let event of this.videoEvents) {
+          try {
             this.video.removeEventListener(event, this, { mozSystemGroup: true });
+          } catch (ex) {}
         }
 
         for (let element of this.controlListeners) {
+          try {
             element.item.removeEventListener(element.event, element.func,
               { mozSystemGroup: true });
+          } catch (ex) {}
         }
 
         delete this.controlListeners;