WebCore::Gradient need not have mutable fields.

Source/platform/graphics/Gradient.h

Index: Source/platform/graphics/Gradient.h
diff --git a/Source/platform/graphics/Gradient.h b/Source/platform/graphics/Gradient.h
index 697f8fb0261c96acfb177229cd81325f851e23c1..ff6bf36d34756b0920e91838f58b2baf206d80dc 100644
--- a/Source/platform/graphics/Gradient.h
+++ b/Source/platform/graphics/Gradient.h
@@ -141,14 +141,13 @@ private:
     float m_r0;
     float m_r1;
     float m_aspectRatio; // For elliptical gradient, width / height.
-    mutable Vector<ColorStop, 2> m_stops;
+    Vector<ColorStop, 2> m_stops;
     bool m_radial;
-    mutable bool m_stopsSorted;
+    bool m_stopsSorted;
     bool m_drawInPMColorSpace;
     GradientSpreadMethod m_spreadMethod;
     AffineTransform m_gradientSpaceTransformation;
 
-
     RefPtr<SkShader> m_gradient;
 };