fix pathops fuzz

src/pathops/SkOpEdgeBuilder.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 "SkGeometry.h"
 #include "SkOpEdgeBuilder.h"
 #include "SkReduceOrder.h"
 
@@ skipping 203 matching lines @@
                     SkPath::Verb v2 = SkReduceOrder::Cubic(&cubicPair[3], cStorage[1]);
                     if (v1 != SkPath::kMove_Verb && v2 != SkPath::kMove_Verb) {
                         SkPoint* curve1 = v1 == SkPath::kCubic_Verb ? &cubicPair[0] : cStorage[0];
                         SkPoint* curve2 = v2 == SkPath::kCubic_Verb ? &cubicPair[3] : cStorage[1];
                         for (int index = 0; index < SkPathOpsVerbToPoints(v1); ++index) {
                             force_small_to_zero(&curve1[index]);
                         }
                         for (int index = 0; index < SkPathOpsVerbToPoints(v2); ++index) {
                             force_small_to_zero(&curve2[index]);
                         }
-                        fCurrentContour->addCurve(v1, curve1);
-                        fCurrentContour->addCurve(v2, curve2);
+                        if (SkPath::kLine_Verb != v1 ||
+                                !SkDPoint::ApproximatelyEqual(curve1[0], curve1[1])) {
+                            fCurrentContour->addCurve(v1, curve1);
+                        }
+                        if (SkPath::kLine_Verb != v2 ||
+                                !SkDPoint::ApproximatelyEqual(curve2[0], curve2[1])) {
+                            fCurrentContour->addCurve(v2, curve2);
+                        }
                     } else {
                         fCurrentContour->addCubic(pointsPtr);
                     }
                 } else {
                     fCurrentContour->addCubic(pointsPtr);
                 }
                 } break;
             case SkPath::kClose_Verb:
                 SkASSERT(fCurrentContour);
                 if (!close()) {
                     return false;
                 }
                 continue;
             default:
                 SkDEBUGFAIL("bad verb");
                 return false;
         }
         SkASSERT(fCurrentContour);
         fCurrentContour->debugValidate();
         pointsPtr += SkPathOpsVerbToPoints(verb);
     }
    if (fCurrentContour && fCurrentContour->count() &&!fAllowOpenContours && !close()) {
        return false;
    }
    return true;
 }