[svg] Add support for mask color-interpolation

https://www.w3.org/TR/SVG11/painting.html#ColorInterpolationProperty

Bug: skia:10842
Change-Id: I3e97577ee257c9afe64d924c768c85badbfab07d
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/354220
Commit-Queue: Florin Malita <fmalita@google.com>
Reviewed-by: Tyler Denniston <tdenniston@google.com>
diff --git a/modules/svg/src/SkSVGAttribute.cpp b/modules/svg/src/SkSVGAttribute.cpp
index a7d922d..098dc7b 100644
--- a/modules/svg/src/SkSVGAttribute.cpp
+++ b/modules/svg/src/SkSVGAttribute.cpp
@@ -27,6 +27,7 @@
     result.fVisibility.set(SkSVGVisibility(SkSVGVisibility::Type::kVisible));
 
     result.fColor.set(SkSVGColorType(SK_ColorBLACK));
+    result.fColorInterpolation.set(SkSVGColorspace::kSRGB);
     result.fColorInterpolationFilters.set(SkSVGColorspace::kLinearRGB);
 
     result.fFontFamily.init("Sans");