Replace a window reference with goog.global in goog.events.Online…

…Handler to allow it to work on workers.

RELNOTES: n/a

PiperOrigin-RevId: 528997097
Change-Id: I4bbdbe157348f91083383e75d9d3d0183904cdda

closure/goog/events/onlinehandler.js

@@ -41,8 +41,11 @@ goog.events.OnlineHandler = function() {
    */
   this.eventHandler_ = new goog.events.EventHandler(this);
 
+  // Note: On workers, these events are not supported on all browsers. See
+  // https://developer.mozilla.org/en-US/docs/Web/API/WorkerGlobalScope/online_event#browser_compatibility
   this.eventHandler_.listen(
-      window, [goog.events.EventType.ONLINE, goog.events.EventType.OFFLINE],
+      goog.global,
+      [goog.events.EventType.ONLINE, goog.events.EventType.OFFLINE],
       this.handleChange_);
 };
 goog.inherits(goog.events.OnlineHandler, goog.events.EventTarget);