Add an API to set the ColorFilter on a Paint object.

sky/engine/core/painting/ColorFilter.h

Index: sky/engine/core/painting/ColorFilter.h
diff --git a/sky/engine/core/painting/ColorFilter.h b/sky/engine/core/painting/ColorFilter.h
new file mode 100644
index 0000000000000000000000000000000000000000..c62c4e1118a934128f3f9361d3fb2391ed0be2d3
--- /dev/null
+++ b/sky/engine/core/painting/ColorFilter.h
@@ -0,0 +1,31 @@
+// Copyright 2015 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 SKY_ENGINE_CORE_PAINTING_COLORFILTER_H_
+#define SKY_ENGINE_CORE_PAINTING_COLORFILTER_H_
+
+#include "sky/engine/tonic/dart_wrappable.h"
+#include "sky/engine/wtf/PassRefPtr.h"
+#include "sky/engine/wtf/RefCounted.h"
+#include "third_party/skia/include/core/SkColorFilter.h"
+
+namespace blink {
+
+class ColorFilter : public RefCounted<ColorFilter>, public DartWrappable {
+  DEFINE_WRAPPERTYPEINFO();
+ public:
+  ~ColorFilter() override;
+  static PassRefPtr<ColorFilter> create(unsigned color, unsigned transfer_mode);
+
+  SkColorFilter* filter() { return filter_.get(); }
+
+ private:
+  ColorFilter(PassRefPtr<SkColorFilter> filter);
+
+  RefPtr<SkColorFilter> filter_;
+};
+
+} // namespace blink
+
+#endif  // SKY_ENGINE_CORE_PAINTING_COLORFILTER_H_