Support colors w/ alpha in SVG 'stop' elements and 'feFlood'

Source/core/svg/SVGStopElement.cpp

Index: Source/core/svg/SVGStopElement.cpp
diff --git a/Source/core/svg/SVGStopElement.cpp b/Source/core/svg/SVGStopElement.cpp
index b3d85099a4449941e0ddf9bf2f690241d078f90d..52201d89d16f72472063f6091d3a52e72e1271d7 100644
--- a/Source/core/svg/SVGStopElement.cpp
+++ b/Source/core/svg/SVGStopElement.cpp
@@ -115,7 +115,7 @@ Color SVGStopElement::stopColorIncludingOpacity() const
         return Color(Color::transparent, true); // Transparent black.
 
     const SVGRenderStyle* svgStyle = style->svgStyle();
-    return colorWithOverrideAlpha(svgStyle->stopColor().rgb(), svgStyle->stopOpacity());
+    return svgStyle->stopColor().combineWithAlpha(svgStyle->stopOpacity());
 }
 
 }