Have bindings layer assume and insist that all interface types are GCed.

third_party/WebKit/Source/modules/webmidi/MIDIPort.idl

 /*
  * Copyright (C) 2013 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 29 matching lines @@
 };
 
 enum MIDIPortType {
     "input",
     "output"
 };
 
 [
     ActiveScriptWrappable,
     DependentLifetime,
-    GarbageCollected,
 ] interface MIDIPort : EventTarget {
     readonly attribute MIDIPortConnectionState connection;
     readonly attribute DOMString id;
     readonly attribute DOMString manufacturer;
     readonly attribute DOMString name;
     readonly attribute MIDIPortDeviceState state;
     readonly attribute MIDIPortType type;
     readonly attribute DOMString version;
 
     attribute EventHandler onstatechange;
 
     [CallWith=ScriptState] Promise open();
     [CallWith=ScriptState] Promise close();
 };