fix bugs found by computing flat clips in 800K skps

src/pathops/SkPathOpsLine.h

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #ifndef SkPathOpsLine_DEFINED
 #define SkPathOpsLine_DEFINED
 
 #include "SkPathOpsPoint.h"
@@ skipping 12 matching lines @@
     static SkDLine SubDivide(const SkPoint a[2], double t1, double t2) {
         SkDLine line;
         line.set(a);
         return line.subDivide(t1, t2);
     }
 
     double exactPoint(const SkDPoint& xy) const;
     static double ExactPointH(const SkDPoint& xy, double left, double right, double y);
     static double ExactPointV(const SkDPoint& xy, double top, double bottom, double x);
     double isLeft(const SkDPoint& pt) const;
-    double nearPoint(const SkDPoint& xy) const;
+    double nearPoint(const SkDPoint& xy, bool* unequal) const;
     bool nearRay(const SkDPoint& xy) const;
     static double NearPointH(const SkDPoint& xy, double left, double right, double y);
     static double NearPointV(const SkDPoint& xy, double top, double bottom, double x);
     static bool NearRay(double dx1, double dy1, double dx2, double dy2);
     SkDPoint ptAtT(double t) const;
     SkDLine subDivide(double t1, double t2) const;
 
     void dump() const;
 private:
     SkDVector tangent() const { return fPts[0] - fPts[1]; }
 };
 
 #endif