fix bugs found by computing flat clips in 800K skps

tests/PathOpsAngleIdeas.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #include "PathOpsTestCommon.h"
 #include "SkIntersections.h"
 #include "SkOpSegment.h"
 #include "SkPathOpsTriangle.h"
@@ skipping 408 matching lines @@
     shortQuad[2] = quad[2].asSkPoint();
     PathOpsSegmentTester::ConstructQuad(result, shortQuad);
 }
 
 static void testQuadAngles(skiatest::Reporter* reporter, const SkDQuad& quad1, const SkDQuad& quad2,
         int testNo) {
     SkPoint shortQuads[2][3];
     SkOpSegment seg[2];
     makeSegment(quad1, shortQuads[0], &seg[0]);
     makeSegment(quad2, shortQuads[1], &seg[1]);
-    int realOverlap = PathOpsAngleTester::ConvexHullOverlaps(seg[0].angle(0), seg[1].angle(0));
+    int realOverlap = PathOpsAngleTester::ConvexHullOverlaps(*seg[0].debugLastAngle(),
+            *seg[1].debugLastAngle());
     const SkDPoint& origin = quad1[0];
     REPORTER_ASSERT(reporter, origin == quad2[0]);
     double a1s = atan2(origin.fY - quad1[1].fY, quad1[1].fX - origin.fX);
     double a1e = atan2(origin.fY - quad1[2].fY, quad1[2].fX - origin.fX);
     double a2s = atan2(origin.fY - quad2[1].fY, quad2[1].fX - origin.fX);
     double a2e = atan2(origin.fY - quad2[2].fY, quad2[2].fX - origin.fX);
     bool oldSchoolOverlap = radianBetween(a1s, a2s, a1e)
         || radianBetween(a1s, a2e, a1e) || radianBetween(a2s, a1s, a2e)
         || radianBetween(a2s, a1e, a2e);
     int overlap = quadHullsOverlap(reporter, quad1, quad2);
@@ skipping 97 matching lines @@
         SkASSERT(SkScalarSignAsInt(SkDoubleToScalar(midXray))
             == SkScalarSignAsInt(SkDoubleToScalar(vDir[sIndex])));
         firstInside = (rayDist > endDist) ^ (sIndex == 0) ^ (vDir[sIndex] < 0);
     } else if (overlap >= 0) {
         return;  // answer has already been determined
     } else {
         firstInside = checkParallel(reporter, quad1, quad2);
     }
     if (overlap < 0) {
         SkDEBUGCODE(int realEnds =)
-                PathOpsAngleTester::EndsIntersect(seg[0].angle(0), seg[1].angle(0));
+                PathOpsAngleTester::EndsIntersect(*seg[0].debugLastAngle(),
+                *seg[1].debugLastAngle());
         SkASSERT(realEnds == (firstInside ? 1 : 0));
     }
     bruteForce(reporter, quad1, quad2, firstInside);
 }
 
 DEF_TEST(PathOpsAngleOverlapHullsOne, reporter) {
 //    gPathOpsAngleIdeasVerbose = true;
     const SkDQuad quads[] = {
 {{{939.4808349609375, 914.355224609375}, {-357.7921142578125, 590.842529296875}, {736.8936767578125, -350.717529296875}}},
 {{{939.4808349609375, 914.355224609375}, {-182.85418701171875, 634.4552001953125}, {-509.62615966796875, 576.1182861328125}}}
@@ skipping 291 matching lines @@
             step /= 2;
         }
 #ifdef SK_DEBUG
 //        DumpQ(q1, q2, 999);
 #endif
     }
     if (gPathOpsAngleIdeasVerbose) {
         SkDebugf("maxR=%1.9g\n", maxR);
     }
 }