fix pathops fuzz failures

src/pathops/SkIntersections.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 "SkIntersections.h"
 
 int SkIntersections::closestTo(double rangeStart, double rangeEnd, const SkDPoint& testPt,
@@ skipping 69 matching lines @@
         int clearMask = ~((1 << index) - 1);
         fIsCoincident[0] += fIsCoincident[0] & clearMask;
         fIsCoincident[1] += fIsCoincident[1] & clearMask;
     }
     fPt[index] = pt;
     SkASSERT(one >= 0 && one <= 1);
     SkASSERT(two >= 0 && two <= 1);
     fT[0][index] = one;
     fT[1][index] = two;
     ++fUsed;
+    SkASSERT(fUsed <= SK_ARRAY_COUNT(fPt));
     return index;
 }
 
 void SkIntersections::insertNear(double one, double two, const SkDPoint& pt1, const SkDPoint& pt2) {
     SkASSERT(one == 0 || one == 1);
     SkASSERT(two == 0 || two == 1);
     SkASSERT(pt1 != pt2);
     fNearlySame[one ? 1 : 0] = true;
     (void) insert(one, two, pt1);
     fPt2[one ? 1 : 0] = pt2;
@@ skipping 50 matching lines @@
     }
     memmove(&fPt[index], &fPt[index + 1], sizeof(fPt[0]) * remaining);
     memmove(&fT[0][index], &fT[0][index + 1], sizeof(fT[0][0]) * remaining);
     memmove(&fT[1][index], &fT[1][index + 1], sizeof(fT[1][0]) * remaining);
 //    SkASSERT(fIsCoincident[0] == 0);
     int coBit = fIsCoincident[0] & (1 << index);
     fIsCoincident[0] -= ((fIsCoincident[0] >> 1) & ~((1 << index) - 1)) + coBit;
     SkASSERT(!(coBit ^ (fIsCoincident[1] & (1 << index))));
     fIsCoincident[1] -= ((fIsCoincident[1] >> 1) & ~((1 << index) - 1)) + coBit;
 }