Consolidate some text shadow code.

Source/core/rendering/style/ShadowList.h

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 15 matching lines @@
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef ShadowList_h
 #define ShadowList_h
 
 #include "core/rendering/style/ShadowData.h"
 #include "platform/geometry/LayoutRect.h"
+#include "platform/graphics/DrawLooperBuilder.h"
+#include "wtf/PassOwnPtr.h"
 #include "wtf/RefCounted.h"
 #include "wtf/Vector.h"
 
 namespace WebCore {
 
 class FloatRect;
 class LayoutRect;
 
 typedef Vector<ShadowData, 1> ShadowDataVector;
 
 // These are used to store shadows in specified order, but we usually want to
 // iterate over them backwards as the first-specified shadow is painted on top.
 class ShadowList : public RefCounted<ShadowList> {
 public:
     // This consumes passed in vector.
     static PassRefPtr<ShadowList> adopt(ShadowDataVector& shadows)
     {
         return adoptRef(new ShadowList(shadows));
     }
     const ShadowDataVector& shadows() const { return m_shadows; }
     bool operator==(const ShadowList& o) const { return m_shadows == o.m_shadows; }
     bool operator!=(const ShadowList& o) const { return !(*this == o); }
 
     static PassRefPtr<ShadowList> blend(const ShadowList* from, const ShadowList* to, double progress);
 
     void adjustRectForShadow(LayoutRect&, float additionalOutlineSize = 0) const;
     void adjustRectForShadow(FloatRect&, float additionalOutlineSize = 0) const;
 
+    PassOwnPtr<DrawLooperBuilder> createDrawLooper(DrawLooperBuilder::ShadowAlphaMode, bool isHorizontal = true) const;
+
 private:
     ShadowList(ShadowDataVector& shadows)
     {
         // If we have no shadows, we use a null ShadowList
         ASSERT(!shadows.isEmpty());
         m_shadows.swap(shadows);
         m_shadows.shrinkToFit();
     }
     ShadowDataVector m_shadows;
 };
 
 } // namespace WebCore
 
 #endif // ShadowList_h