Oilpan: add transition types to remaining Fetch and ServiceWorker objects

Source/modules/serviceworkers/Headers.idl

 // Copyright 2014 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.
 
 // http://fetch.spec.whatwg.org/#headers-class
 [
     Constructor,
     Constructor(Headers input),
     Constructor(Dictionary input),
     RuntimeEnabled=ServiceWorker,
     Exposed=ServiceWorker,
-    RaisesException=Constructor
+    RaisesException=Constructor,
+    WillBeGarbageCollected,
 ] interface Headers {
     [RaisesException] void append(ByteString name, ByteString value);
     [ImplementedAs=remove, RaisesException] void delete(ByteString key);
     [RaisesException] ByteString? get(ByteString key);
     [RaisesException] sequence<ByteString> getAll(ByteString name);
     [RaisesException] boolean has(ByteString key);
     [RaisesException] void set(ByteString key, ByteString value);
 
     // The following are not defined in the spec.
     // FIXME: We should implement Headers.prototype[Symbol.iterator] instead of
     // forEach and size.
     // https://www.w3.org/Bugs/Public/show_bug.cgi?id=26102
     readonly attribute unsigned long size;
     void forEach(HeadersForEachCallback callback, optional any thisArg);
 };