Remove EME and MSE from RuntimeEnabledFeatures.

third_party/WebKit/Source/modules/encryptedmedia/MediaKeyMessageEvent.idl

 /*
  * Copyright (C) 2012 Google Inc.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 14 matching lines @@
 
 // https://w3c.github.io/encrypted-media/#mediakeymessageevent
 
 enum MediaKeyMessageType {
     "license-request",
     "license-renewal",
     "license-release"
 };
 
 [
-    Constructor(DOMString type, optional MediaKeyMessageEventInit eventInitDict),
-    RuntimeEnabled=EncryptedMedia
+    Constructor(DOMString type, optional MediaKeyMessageEventInit eventInitDict)
 ] interface MediaKeyMessageEvent : Event {
     readonly attribute MediaKeyMessageType messageType;
     readonly attribute ArrayBuffer message;
 };