Ensure the permissions DOMTokenList is initialized before access

third_party/WebKit/Source/core/html/HTMLIFrameElement.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Simon Hausmann <hausmann@kde.org>
  * Copyright (C) 2004, 2006, 2008, 2009 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 22 matching lines @@
 
 namespace blink {
 
 class CORE_EXPORT HTMLIFrameElement final : public HTMLFrameElementBase {
     DEFINE_WRAPPERTYPEINFO();
 public:
     DECLARE_NODE_FACTORY(HTMLIFrameElement);
     DECLARE_VIRTUAL_TRACE();
     ~HTMLIFrameElement() override;
     DOMTokenList* sandbox() const;
-    DOMTokenList* permissions() const;
+    DOMTokenList* permissions();

[esprehn, 2016/07/27 06:05:56]

This is logically const, I'd const cast in the method. That it's lazy allocated
is a detail that's not relevant to users.

[raymes, 2016/07/27 06:13:45]

Done.

 
     void sandboxValueWasSet();
     void permissionsValueWasSet();
 
 private:
     explicit HTMLIFrameElement(Document&);
 
     void parseAttribute(const QualifiedName&, const AtomicString&, const AtomicString&) override;
     bool isPresentationAttribute(const QualifiedName&) const override;
     void collectStyleForPresentationAttribute(const QualifiedName&, const AtomicString&, MutableStylePropertySet*) override;
@@ skipping 23 matching lines @@
     Member<HTMLIFrameElementPermissions> m_permissions;
 
     WebVector<WebPermissionType> m_delegatedPermissions;
 
     ReferrerPolicy m_referrerPolicy;
 };
 
 } // namespace blink
 
 #endif // HTMLIFrameElement_h