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

sky/engine/core/painting/Paint.cpp

 // 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.
 
 #include "sky/engine/config.h"
 #include "sky/engine/core/painting/Paint.h"
 
+#include "sky/engine/core/painting/ColorFilter.h"
 #include "sky/engine/core/painting/DrawLooper.h"
 
 namespace blink {
 
 Paint::Paint()
 {
 }
 
 Paint::~Paint()
 {
 }
 
 void Paint::setDrawLooper(DrawLooper* looper)
 {
     ASSERT(looper);
     m_paint.setLooper(looper->looper());
 }
 
+void Paint::setColorFilter(ColorFilter* filter)
+{
+    ASSERT(filter);
+    m_paint.setColorFilter(filter->filter());
+}
+
 } // namespace blink