Backed out 2 changesets (bug 1266437, bug 1232918) for causing mochitest failures in test_autoplay_policy_key_blacklist.html CLOSED TREE

Backed out changeset 33e3c6593d4b (bug 1232918)
Backed out changeset 1b56e99dd221 (bug 1266437)

dom/html/HTMLInputElement.cpp

@@ -3537,16 +3537,8 @@ nsresult HTMLInputElement::MaybeInitPickers(EventChainPostVisitor& aVisitor) {
  */
 static bool IgnoreInputEventWithModifier(const WidgetInputEvent& aEvent,
                                          bool ignoreControl) {
-  return (ignoreControl && aEvent.IsControl()) ||
-         aEvent.IsAltGraph()
-#if defined(XP_WIN) || defined(MOZ_WIDGET_GTK)
-         // Meta key is the Windows Logo key on Windows and Linux which may
-         // assign some special meaning for the events while it's pressed.
-         // On the other hand, it's a normal modifier in macOS and Android.
-         // Therefore, We should ignore it only in Win/Linux.
-         || aEvent.IsMeta()
-#endif
-         || aEvent.IsFn();
+  return (ignoreControl && aEvent.IsControl()) || aEvent.IsAltGraph() ||
+         aEvent.IsFn() || aEvent.IsOS();
 }
 
 bool HTMLInputElement::StepsInputValue(