Oilpan: move AsyncMethodRunner to the heap.

third_party/WebKit/Source/core/css/FontFaceSet.h

 /*
  * 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:
  *
  * 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 157 matching lines @@
     using ReadyProperty = ScriptPromiseProperty<RawPtrWillBeMember<FontFaceSet>, RawPtrWillBeMember<FontFaceSet>, Member<DOMException>>;
 
     WillBeHeapHashSet<RefPtrWillBeMember<FontFace>> m_loadingFonts;
     bool m_shouldFireLoadingEvent;
     bool m_isLoading;
     PersistentWillBeMember<ReadyProperty> m_ready;
     FontFaceArray m_loadedFonts;
     FontFaceArray m_failedFonts;
     WillBeHeapListHashSet<RefPtrWillBeMember<FontFace>> m_nonCSSConnectedFaces;
 
-    AsyncMethodRunner<FontFaceSet> m_asyncRunner;
+    PersistentWillBeMember<AsyncMethodRunner<FontFaceSet>> m_asyncRunner;
 
     FontLoadHistogram m_histogram;
 };
 
 } // namespace blink
 
 #endif // FontFaceSet_h