Move SkPaint mangement for 2D canvas into CanvasRenderingContext2DState

Source/platform/graphics/DrawLooperBuilder.cpp

Index: Source/platform/graphics/DrawLooperBuilder.cpp
diff --git a/Source/platform/graphics/DrawLooperBuilder.cpp b/Source/platform/graphics/DrawLooperBuilder.cpp
index 3b0a8f45ae0f94efb0a724f92aa75483c59f84f7..1b30b6767fbf6cbb01c36da4f8f302ee4259d7aa 100644
--- a/Source/platform/graphics/DrawLooperBuilder.cpp
+++ b/Source/platform/graphics/DrawLooperBuilder.cpp
@@ -33,6 +33,7 @@
 
 #include "platform/geometry/FloatSize.h"
 #include "platform/graphics/Color.h"
+#include "platform/graphics/skia/SkiaUtils.h"
 #include "third_party/skia/include/core/SkColor.h"
 #include "third_party/skia/include/core/SkColorFilter.h"
 #include "third_party/skia/include/core/SkDrawLooper.h"
@@ -63,13 +64,6 @@ void DrawLooperBuilder::addUnmodifiedContent()
     m_skDrawLooperBuilder.addLayerOnTop(info);
 }
 
-// This replicates the old skia behavior when it used to take radius for blur. Now it takes sigma.
-static SkScalar RadiusToSigma(SkScalar radius)
-{
-    SkASSERT(radius > 0);
-    return 0.57735f * radius + 0.5f;
-}
-
 void DrawLooperBuilder::addShadow(const FloatSize& offset, float blur, const Color& color,
     ShadowTransformMode shadowTransformMode, ShadowAlphaMode shadowAlphaMode)
 {
@@ -101,7 +95,7 @@ void DrawLooperBuilder::addShadow(const FloatSize& offset, float blur, const Col
     SkPaint* paint = m_skDrawLooperBuilder.addLayerOnTop(info);
 
     if (blur) {
-        const SkScalar sigma = RadiusToSigma(blur / 2);
+        const SkScalar sigma = skBlurRadiusToSigma(blur);
         uint32_t mfFlags = SkBlurMaskFilter::kHighQuality_BlurFlag;
         if (shadowTransformMode == ShadowIgnoresTransforms)
             mfFlags |= SkBlurMaskFilter::kIgnoreTransform_BlurFlag;