add gpu impl for shadermaskfilter

adds MulChildAlphaByInput
renames MulOutputByInputAlpha --> MulChildByInputAlpha

Bug: skia:7500
Change-Id: Ic0615d4d23a887fbee510901ed77a36f98a1b11d
Reviewed-on: https://skia-review.googlesource.com/102440
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Mike Reed <reed@google.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/gm/shadermaskfilter.cpp b/gm/shadermaskfilter.cpp
index 8011b45d41..73a9cda65f 100644
--- a/gm/shadermaskfilter.cpp
+++ b/gm/shadermaskfilter.cpp
@@ -22,6 +22,7 @@ static void draw_masked_image(SkCanvas* canvas, const SkImage* image, SkScalar x
         mf = SkMaskFilter::MakeCompose(outer, mf);
     }
     paint.setMaskFilter(mf);
+    paint.setAntiAlias(true);
     canvas->drawImage(image, x, y, &paint);
 }
 
@@ -45,6 +46,7 @@ DEF_SIMPLE_GM(shadermaskfilter_gradient, canvas, 512, 512) {
     SkPaint paint;
     paint.setMaskFilter(mf);
     paint.setColor(SK_ColorRED);
+    paint.setAntiAlias(true);
     canvas->drawOval(r, paint);
 }