Added CSSPropertyAPI and CSS padding properties which implement this API

third_party/WebKit/Source/core/css/properties/CSSPropertyAPIPadding.h

+// Copyright 2016 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 CSSPropertyAPIPadding_h
+#define CSSPropertyAPIPadding_h
+
+#include "core/CSSPropertyNames.h"
+#include "core/css/properties/CSSPropertyAPI.h"
+
+namespace blink {
+
+// TODO(aazzam): Generate API .h files
+
+class CSSParserTokenRange;
+class CSSParserContext;
+
+class CSSPropertyAPIWebkitPadding : public CSSPropertyAPI {
+ public:
+  static const CSSValue* parseSingleValue(CSSParserTokenRange&,
+                                          const CSSParserContext&);
+};
+
+}  // namespace blink
+
+#endif  // CSSPropertyAPIPadding_h