Use ShadowData in DropShadowFilterOperation

third_party/WebKit/Source/core/style/ShadowData.cpp

 /*
  * Copyright (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights
  * reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 24 matching lines @@
                              double progress,
                              const Color& currentColor) const {
   ASSERT(style() == from.style());
   return ShadowData(blink::blend(from.location(), location(), progress),
                     clampTo(blink::blend(from.blur(), blur(), progress), 0.0f),
                     blink::blend(from.spread(), spread(), progress), style(),
                     blink::blend(from.color().resolve(currentColor),
                                  color().resolve(currentColor), progress));
 }
 
+ShadowData ShadowData::neutralValue() {
+  return ShadowData(FloatPoint(0, 0), 0, 0, Normal,
+                    StyleColor(Color::transparent));
+}
+
 }  // namespace blink