fix msan bug in pathops

src/pathops/SkPathOpsCurve.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #include "SkPathOpsBounds.h"
 #include "SkPathOpsRect.h"
 #include "SkPathOpsCurve.h"
 
@@ skipping 36 matching lines @@
     }
     double largest = SkTMax(SkTMax(maxX, maxY), -SkTMin(minX, minY));
     if (!AlmostEqualUlps_Pin(largest, largest + minDist)) { // is distance within ULPS tolerance?
         return -1;
     }
     return SkPinT(i[0][minIndex]);
 }
 
 void SkDCurve::offset(SkPath::Verb verb, const SkDVector& off) {
     int count = SkPathOpsVerbToPoints(verb);
-    for (int index = 0; index < count; ++index) {
+    for (int index = 0; index <= count; ++index) {
         fCubic.fPts[index] += off;
     }
 }
 
 void SkDCurve::setConicBounds(const SkPoint curve[3], SkScalar curveWeight,
         double tStart, double tEnd, SkPathOpsBounds* bounds) {
     SkDConic dCurve;
     dCurve.set(curve, curveWeight);
     SkDRect dRect;
     dRect.setBounds(dCurve, fConic, tStart, tEnd);
@@ skipping 26 matching lines @@
     fSweep[0] = fCurve[1] - fCurve[0];
     if (SkPath::kLine_Verb == verb) {
         fSweep[1] = fSweep[0];
         fIsCurve = false;
         return;
     }
     fSweep[1] = fCurve[2] - fCurve[0];
     // OPTIMIZE: I do the following float check a lot -- probably need a
     // central place for this val-is-small-compared-to-curve check
     double maxVal = 0;
-    for (int index = 0; index < SkPathOpsVerbToPoints(verb); ++index) {
+    for (int index = 0; index <= SkPathOpsVerbToPoints(verb); ++index) {
         maxVal = SkTMax(maxVal, SkTMax(SkTAbs(fCurve[index].fX),
                 SkTAbs(fCurve[index].fY)));
     }
     {
         if (SkPath::kCubic_Verb != verb) {
             if (roughly_zero_when_compared_to(fSweep[0].fX, maxVal)
                     && roughly_zero_when_compared_to(fSweep[0].fY, maxVal)) {
                 fSweep[0] = fSweep[1];
             }
             goto setIsCurve;
@@ skipping 21 matching lines @@
         if (s3x2 * s2x1 < 0) {
             SkASSERT(s2x1 * s1x3 > 0);
             fSweep[0] = fSweep[1];
             fOrdered = false;
         }
         fSweep[1] = thirdSweep;
     }
 setIsCurve:
     fIsCurve = fSweep[0].crossCheck(fSweep[1]) != 0;
 }