Add the NonElementParentNode interface

Source/core/dom/NonElementParentNode.h

+// 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.
+
+#ifndef NonElementParentNode_h
+#define NonElementParentNode_h
+
+#include "core/dom/Document.h"
+#include "core/dom/DocumentFragment.h"
+
+namespace blink {
+
+class NonElementParentNode {

[haraken, 2015/03/01 08:53:07]

Add final.

[philipj_slow, 2015/03/01 15:32:14]

Hmm, does that do anything on a class that inherits nothing and has no virtual
members? Note that NonDocumentTypeChildNode does not have final, so whatever the
rule is I'd like to apply it consistently. I'm not really sure what to take away
from the blink-dev discussion:
https://groups.google.com/a/chromium.org/forum/#!topic/chromium-dev/VTNZzizN0zo

+public:
+    static Element* getElementById(Document& document, const AtomicString& id)
+    {
+        return document.getElementById(id);
+    }
+
+    static Element* getElementById(DocumentFragment& fragment, const AtomicString& id)
+    {
+        return fragment.getElementById(id);
+    }
+};
+
+} // namespace blink
+
+#endif // NonElementParentNode_h