Maintain SkPaint in GraphicsContextState.

Source/platform/graphics/Gradient.h

 /*
  * Copyright (C) 2006, 2007, 2008, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Alp Toker <alp@atoker.com>
  * Copyright (C) 2008 Torch Mobile, Inc.
  * 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:
  * 1. Redistributions of source code must retain the above copyright
@@ skipping 54 matching lines @@
         float blue;
         float alpha;
 
         ColorStop() : stop(0), red(0), green(0), blue(0), alpha(0) { }
         ColorStop(float s, float r, float g, float b, float a) : stop(s), red(r), green(g), blue(b), alpha(a) { }
     };
     void addColorStop(const ColorStop&);
     void addColorStop(float, const Color&);
 
     bool hasAlpha() const;
+    bool shaderChanged() const { return m_shaderChanged; }

[f(malita), 2014/03/04 14:23:47]

How about

  return !m_shader?

Gradient already takes care of tracking/invalidating its shader, I think we can
use that.

[Stephen Chennney, 2014/03/04 14:47:10]

Done.

 
     bool isRadial() const { return m_radial; }
     bool isZeroSize() const { return m_p0.x() == m_p1.x() && m_p0.y() == m_p1.y() && (!m_radial || m_r0 == m_r1); }
 
     const FloatPoint& p0() const { return m_p0; }
     const FloatPoint& p1() const { return m_p1; }
 
     void setP0(const FloatPoint& p)
     {
         if (m_p0 == p)
@@ skipping 43 matching lines @@
     AffineTransform gradientSpaceTransform() { return m_gradientSpaceTransformation; }
 
 private:
     Gradient(const FloatPoint& p0, const FloatPoint& p1);
     Gradient(const FloatPoint& p0, float r0, const FloatPoint& p1, float r1, float aspectRatio);
 
     void destroyShader();
 
     void sortStopsIfNecessary();
 
-    // Keep any parameters relevant to rendering in sync with the structure in Gradient::hash().
-    bool m_radial;
     FloatPoint m_p0;
     FloatPoint m_p1;
     float m_r0;
     float m_r1;
     float m_aspectRatio; // For elliptical gradient, width / height.
     mutable Vector<ColorStop, 2> m_stops;
+    bool m_radial;
     mutable bool m_stopsSorted;
+    bool m_shaderChanged;

[f(malita), 2014/03/03 22:46:21]

Looks like we can consolidate these three bools + the one below in a bitfield.

[Stephen Chennney, 2014/03/04 13:20:36]

I missed the odd one at the bottom. So yes.

[Stephen Chennney, 2014/03/04 14:47:10]

Done.

     GradientSpreadMethod m_spreadMethod;
     AffineTransform m_gradientSpaceTransformation;
 
     bool m_drawInPMColorSpace;
 
     RefPtr<SkShader> m_gradient;
 };
 
 } // namespace WebCore
 
 #endif