Added CSSPropertyOffsetPathUtils which holds shared parsing logic.

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

Index: third_party/WebKit/Source/core/css/properties/CSSPropertyOffsetPathUtils.h
diff --git a/third_party/WebKit/Source/core/css/properties/CSSPropertyOffsetPathUtils.h b/third_party/WebKit/Source/core/css/properties/CSSPropertyOffsetPathUtils.h
new file mode 100644
index 0000000000000000000000000000000000000000..dc00e532d1510cfdf04e1d792bf40911994b831b
--- /dev/null
+++ b/third_party/WebKit/Source/core/css/properties/CSSPropertyOffsetPathUtils.h
@@ -0,0 +1,26 @@
+// Copyright 2017 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 CSSPropertyOffsetPathUtils_h
+#define CSSPropertyOffsetPathUtils_h
+
+#include "platform/wtf/Allocator.h"
+
+namespace blink {
+
+class CSSParserContext;
+class CSSParserTokenRange;
+class CSSValue;
+
+class CSSPropertyOffsetPathUtils {
+  STATIC_ONLY(CSSPropertyOffsetPathUtils);
+  static CSSValue* ConsumeOffsetPath(CSSParserTokenRange&,
+                                     const CSSParserContext*,
+                                     bool);
+  static CSSValue* ConsumePathOrNone(CSSParserTokenRange&);
+};
+
+}  // namespace blink
+
+#endif  // CSSPropertyOffsetPathUtils_h