diff -r 000000000000 -r 6474c204b198 content/base/public/nsIDocumentInlines.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/content/base/public/nsIDocumentInlines.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,18 @@
+/* -*- Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil; tab-width: 8; -*- */
+/* vim: set sw=2 sts=2 ts=8 et tw=80 : */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+#ifndef nsIDocumentInlines_h
+#define nsIDocumentInlines_h
+
+#include "nsIDocument.h"
+#include "mozilla/dom/HTMLBodyElement.h"
+
+inline mozilla::dom::HTMLBodyElement*
+nsIDocument::GetBodyElement()
+{
+  return static_cast<mozilla::dom::HTMLBodyElement*>(GetHtmlChildElement(nsGkAtoms::body));
+}
+
+#endif // nsIDocumentInlines_h