compute initial winding from projected rays

src/pathops/SkPathOpsPoint.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #include "SkPathOpsPoint.h"
 
 SkDVector operator-(const SkDPoint& a, const SkDPoint& b) {
     SkDVector v = {a.fX - b.fX, a.fY - b.fY};
     return v;
 }
-
-SkDPoint operator+(const SkDPoint& a, const SkDVector& b) {
-    SkDPoint v = {a.fX + b.fX, a.fY + b.fY};
-    return v;
-}