Sky: Added radial gradients.

sky/engine/core/painting/CanvasGradient.h

 // 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_CANVASGRADIENT_H_
 #define SKY_ENGINE_CORE_PAINTING_CANVASGRADIENT_H_
 
 #include "sky/engine/core/painting/CanvasColor.h"
 #include "sky/engine/core/painting/Point.h"
 #include "sky/engine/core/painting/Shader.h"
 #include "sky/engine/tonic/dart_wrappable.h"
 #include "third_party/skia/include/effects/SkGradientShader.h"
 
 namespace blink {
 
 class CanvasGradient : public Shader {
     DEFINE_WRAPPERTYPEINFO();
  public:
   ~CanvasGradient() override;
-  static PassRefPtr<CanvasGradient> create(int type,
-                                           const Vector<Point>& end_points,
-                                           const Vector<SkColor>& colors,
-                                           const Vector<float>& color_stops);
+  static PassRefPtr<CanvasGradient> create();
+
+  void initLinear(const Vector<Point>& end_points,
+                  const Vector<SkColor>& colors,
+                  const Vector<float>& color_stops);
+  void initRadial(const Point& center,
+                  double radius,
+                  const Vector<SkColor>& colors,
+                  const Vector<float>& color_stops);
 
  private:
-  CanvasGradient(PassRefPtr<SkShader> shader);
+  CanvasGradient();
 };
 
 } // namespace blink
 
 #endif  // SKY_ENGINE_CORE_PAINTING_CANVASGRADIENT_H_