Roll 50: Copied IDLs, PYTHON scripts from WebKit removed deleted files in WebCore

modules/encryptedmedia/MediaKeys.idl

 /*
  * Copyright (C) 2013 Apple 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 11 matching lines @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 enum MediaKeySessionType {
     "temporary",
     "persistent-license",
 };
 
 [
-    ActiveDOMObject,
+    DependentLifetime,
     RuntimeEnabled=EncryptedMedia,
     GarbageCollected,
-    TypeChecking=Interface
 ] interface MediaKeys {
     [CallWith=ScriptState, RaisesException] MediaKeySession createSession(optional MediaKeySessionType sessionType = "temporary");
 
     [CallWith=ScriptState] Promise<void> setServerCertificate(BufferSource serverCertificate);
 };