Backed out changeset bd45588af02e (bug 1314125) for timing out in browser_permission_doorhanger.js on e10s. r=backout

toolkit/modules/PopupNotifications.jsm

@@ -1054,7 +1054,11 @@ PopupNotifications.prototype = {
   },
 
   _isActiveBrowser: function (browser) {
-    return this.tabbrowser.selectedBrowser == browser;
+    // Note: This helper only exists, because in e10s builds,
+    // we can't access the docShell of a browser from chrome.
+    return browser.docShell
+      ? browser.docShell.isActive
+      : (this.window.gBrowser.selectedBrowser == browser);
   },
 
   _onIconBoxCommand: function PopupNotifications_onIconBoxCommand(event) {