Bug 1101482 - fix e10s case for browser_988072_sidebar_events.js, r=intermittentisgone

--HG--
extra : rebase_source : b13a515434002d396f1077f1fc59f43db94f30e8

browser/components/customizableui/test/browser.ini

@@ -130,7 +130,6 @@ skip-if = os == "linux"
 skip-if = e10s # bug 1090635
 [browser_981305_separator_insertion.js]
 [browser_988072_sidebar_events.js]
-skip-if = e10s # bug 1101482 - fails in --run-by-dir
 [browser_989338_saved_placements_not_resaved.js]
 [browser_989751_subviewbutton_class.js]
 [browser_987177_destroyWidget_xul.js]

browser/components/customizableui/test/browser_988072_sidebar_events.js

@@ -80,8 +80,7 @@ let showSidebarPopup = Task.async(function*() {
 
   let subviewShownPromise = subviewShown(subview);
   EventUtils.synthesizeMouseAtCenter(button, {});
-  yield subviewShownPromise;
-  return waitForCondition(() => !subview.panelMultiView.hasAttribute("transitioning"));
+  return subviewShownPromise;
 });
 
 // Check the sidebar widget shows the default items