Fix for aggressive Chrome MSAN

src/core/SkColorSpaceXform.cpp

Index: src/core/SkColorSpaceXform.cpp
diff --git a/src/core/SkColorSpaceXform.cpp b/src/core/SkColorSpaceXform.cpp
index cacb38878cd1cf86c0489b3775b5abea945df16c..fad8cef1738aa3c75ce18f55f97cc1233f3598cd 100644
--- a/src/core/SkColorSpaceXform.cpp
+++ b/src/core/SkColorSpaceXform.cpp
@@ -1097,7 +1097,7 @@ static void color_xform_RGBA(void* dst, const void* vsrc, int len,
             transform_gamut_1(r, g, b, rXgXbX, rYgYbY, rZgZbZ, rgba);
             translate_gamut_1(rTgTbT, rgba);
         } else {
-            rgba = Sk4f(r[0], g[0], b[0], a[0]);
+            rgba = Sk4f(r[0], g[0], b[0], 0.0f);
         }
 
         if (kPremul_SkAlphaType == kAlphaType) {