replace SkBitmap::Config with SkColorType in gms

src/effects/SkBlurMaskFilter.cpp

Index: src/effects/SkBlurMaskFilter.cpp
diff --git a/src/effects/SkBlurMaskFilter.cpp b/src/effects/SkBlurMaskFilter.cpp
index f4d399b80fef48b27f99a273112db77fb723909b..7a202951564f8456267a3b2b11ec5243bdf71d7d 100644
--- a/src/effects/SkBlurMaskFilter.cpp
+++ b/src/effects/SkBlurMaskFilter.cpp
@@ -195,9 +195,7 @@ static bool draw_rrect_into_mask(const SkRRect rrect, SkMask* mask) {
     // FIXME: This code duplicates code in draw_rects_into_mask, below. Is there a
     // clean way to share more code?
     SkBitmap bitmap;
-    bitmap.installPixels(SkImageInfo::MakeA8(mask->fBounds.width(),
-                                             mask->fBounds.height()),
-                         mask->fImage, mask->fRowBytes, NULL, NULL);
+    bitmap.installMaskPixels(*mask);
 
     SkCanvas canvas(bitmap);
     canvas.translate(-SkIntToScalar(mask->fBounds.left()),