add more SK_WARN_UNUSED_RESULT attributes to functions that ignore out-params if they fail

src/core/SkCubicClipper.h

Index: src/core/SkCubicClipper.h
diff --git a/src/core/SkCubicClipper.h b/src/core/SkCubicClipper.h
index 617086edb9c8e61d63517517d7c4127eb9b256d9..f00c09ab5f9c73a009381835ba52f1f23c6e962b 100644
--- a/src/core/SkCubicClipper.h
+++ b/src/core/SkCubicClipper.h
@@ -24,9 +24,9 @@ public:
 
     void setClip(const SkIRect& clip);
 
-    bool clipCubic(const SkPoint src[4], SkPoint dst[4]);
+    bool SK_WARN_UNUSED_RESULT clipCubic(const SkPoint src[4], SkPoint dst[4]);
 
-    static bool ChopMonoAtY(const SkPoint pts[4], SkScalar y, SkScalar* t);
+    static bool SK_WARN_UNUSED_RESULT ChopMonoAtY(const SkPoint pts[4], SkScalar y, SkScalar* t);
 private:
     SkRect      fClip;
 };