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

third_party/WebKit/Source/modules/presentation/PresentationRequest.idl

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // TODO(mlamouri): double-check link after spec changes have landed.
 // https://w3c.github.io/presentation-api/#interface-presentationrequest
 
 [
     ActiveScriptWrappable,
     ConstructorCallWith=ExecutionContext,
     Constructor(DOMString url),
     DependentLifetime,
-    GarbageCollected,
     MeasureAs=PresentationRequestConstructor,
     RaisesException=Constructor,
     RuntimeEnabled=Presentation,
 ] interface PresentationRequest : EventTarget {
     [CallWith=ScriptState, MeasureAs=PresentationRequestStart] Promise<PresentationConnection> start();
     [CallWith=ScriptState, MeasureAs=PresentationRequestReconnect] Promise<PresentationConnection> reconnect(DOMString id);
     [CallWith=ScriptState, MeasureAs=PresentationRequestGetAvailability] Promise<PresentationAvailability> getAvailability();
 
     attribute EventHandler onconnectionavailable;
 };