Sky: Add a DrawLooper interface to the painting API to be used for shadows.

sky/engine/core/painting/DrawLooper.cpp

Index: sky/engine/core/painting/DrawLooper.cpp
diff --git a/sky/engine/core/painting/Paint.cpp b/sky/engine/core/painting/DrawLooper.cpp
similarity index 60%
copy from sky/engine/core/painting/Paint.cpp
copy to sky/engine/core/painting/DrawLooper.cpp
index f3e6fcae0fbd241cca373bde147ae83dce270c6c..b7503d89271cd8dcb6f75d7b6102dc0f3a011002 100644
--- a/sky/engine/core/painting/Paint.cpp
+++ b/sky/engine/core/painting/DrawLooper.cpp
@@ -3,16 +3,15 @@
 // found in the LICENSE file.
 
 #include "sky/engine/config.h"
-#include "sky/engine/core/painting/Paint.h"
+#include "sky/engine/core/painting/DrawLooper.h"
 
 namespace blink {
 
-Paint::Paint()
-{
+DrawLooper::DrawLooper(PassRefPtr<SkDrawLooper> looper)
+    : looper_(looper) {
 }
 
-Paint::~Paint()
-{
+DrawLooper::~DrawLooper() {
 }
 
 } // namespace blink