Use correct gradient calculation for rotated distance fields.

src/gpu/batches/GrAADistanceFieldPathRenderer.cpp

Index: src/gpu/batches/GrAADistanceFieldPathRenderer.cpp
diff --git a/src/gpu/batches/GrAADistanceFieldPathRenderer.cpp b/src/gpu/batches/GrAADistanceFieldPathRenderer.cpp
index 8525eb2fdef513928831a3cdbfa31985e6860eb7..b585de963a97d1e4ab102bfe5d7742a44d687270 100644
--- a/src/gpu/batches/GrAADistanceFieldPathRenderer.cpp
+++ b/src/gpu/batches/GrAADistanceFieldPathRenderer.cpp
@@ -190,8 +190,10 @@ private:
             return;
         }
 
+        const SkMatrix& ctm = this->viewMatrix();
         uint32_t flags = 0;
-        flags |= this->viewMatrix().isSimilarity() ? kSimilarity_DistanceFieldEffectFlag : 0;
+        flags |= ctm.isScaleTranslate() ? kScaleOnly_DistanceFieldEffectFlag : 0;
+        flags |= ctm.isSimilarity() ? kSimilarity_DistanceFieldEffectFlag : 0;
 
         GrTextureParams params(SkShader::kRepeat_TileMode, GrTextureParams::kBilerp_FilterMode);