Consider conical shader opaque if it covers entire plane.

src/effects/gradients/SkTwoPointConicalGradient.h

Index: src/effects/gradients/SkTwoPointConicalGradient.h
diff --git a/src/effects/gradients/SkTwoPointConicalGradient.h b/src/effects/gradients/SkTwoPointConicalGradient.h
index 1358f0b2ac4b85cef506a51c2fe2d57fc1e0d9a6..a78837077bd170a86f8908e4ed1d0e534442c037 100644
--- a/src/effects/gradients/SkTwoPointConicalGradient.h
+++ b/src/effects/gradients/SkTwoPointConicalGradient.h
@@ -23,6 +23,7 @@ struct TwoPtRadial {
     float   fA;
     float   fRadius2;
     float   fRDR;
+    bool    fConeFillsPlane;
 
     void init(const SkPoint& center0, SkScalar rad0,
               const SkPoint& center1, SkScalar rad1);