Issue #2862 - Split the css lowering functionality out to a separate file for easier maintenance

layout/style/CSSNestingLowerer.h

@@ -0,0 +1,19 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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 CSSNestingLowerer_h
+#define CSSNestingLowerer_h
+
+class nsAString;
+
+namespace mozilla {
+namespace css {
+
+bool LowerBasicCSSNesting(const nsAString& aInput, nsAString& aOutput);
+
+} // namespace css
+} // namespace mozilla
+
+#endif // CSSNestingLowerer_h