fix some pathops bugs found in 1M skps

src/pathops/SkPathOpsCommon.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 "SkAddIntersections.h"
 #include "SkOpCoincidence.h"
 #include "SkOpEdgeBuilder.h"
 #include "SkPathOpsCommon.h"
@@ skipping 432 matching lines @@
     SkOpContour* contour = contourList;
     do {
         contour->sortAngles();
     } while ((contour = contour->next()));
 }
 
 bool HandleCoincidence(SkOpContourHead* contourList, SkOpCoincidence* coincidence,
         SkChunkAlloc* allocator) {
     SkOpGlobalState* globalState = contourList->globalState();
     // combine t values when multiple intersections occur on some segments but not others
+    DEBUG_COINCIDENCE_HEALTH(contourList, "start");
     moveMultiples(contourList);
+    DEBUG_COINCIDENCE_HEALTH(contourList, "moveMultiples");
     findCollapsed(contourList);
+    DEBUG_COINCIDENCE_HEALTH(contourList, "findCollapsed");
     // move t values and points together to eliminate small/tiny gaps
     moveNearby(contourList);
+    DEBUG_COINCIDENCE_HEALTH(contourList, "moveNearby");
     align(contourList);  // give all span members common values
+    DEBUG_COINCIDENCE_HEALTH(contourList, "align");
     coincidence->fixAligned();  // aligning may have marked a coincidence pt-t deleted
+    DEBUG_COINCIDENCE_HEALTH(contourList, "fixAligned");
 #if DEBUG_VALIDATE
     globalState->setPhase(SkOpGlobalState::kIntersecting);
 #endif
     // look for intersections on line segments formed by moving end points
     addAlignIntersections(contourList, allocator);
-    coincidence->addMissing(allocator);
+    DEBUG_COINCIDENCE_HEALTH(contourList, "addAlignIntersections");
+    if (coincidence->addMissing(allocator)) {
+        DEBUG_COINCIDENCE_HEALTH(contourList, "addMissing");
+        moveNearby(contourList);
+        DEBUG_COINCIDENCE_HEALTH(contourList, "moveNearby2");
+        align(contourList);  // give all span members common values
+        DEBUG_COINCIDENCE_HEALTH(contourList, "align2");
+        coincidence->fixAligned();  // aligning may have marked a coincidence pt-t deleted
+        DEBUG_COINCIDENCE_HEALTH(contourList, "fixAligned2");
+    }
 #if DEBUG_VALIDATE
     globalState->setPhase(SkOpGlobalState::kWalking);
 #endif
     // check to see if, loosely, coincident ranges may be expanded
     if (coincidence->expand()) {
-        coincidence->addExpanded(allocator  PATH_OPS_DEBUG_VALIDATE_PARAMS(globalState));
+        DEBUG_COINCIDENCE_HEALTH(contourList, "expand1");
+        if (!coincidence->addExpanded(allocator  PATH_OPS_DEBUG_VALIDATE_PARAMS(globalState))) {
+            return false;
+        }
     }
+    DEBUG_COINCIDENCE_HEALTH(contourList, "expand2");
     // the expanded ranges may not align -- add the missing spans
     coincidence->mark();  // mark spans of coincident segments as coincident
+    DEBUG_COINCIDENCE_HEALTH(contourList, "mark1");
     // look for coincidence missed earlier
     if (missingCoincidence(contourList, coincidence, allocator)) {
+        DEBUG_COINCIDENCE_HEALTH(contourList, "missingCoincidence1");
         (void) coincidence->expand();
-        coincidence->addExpanded(allocator  PATH_OPS_DEBUG_VALIDATE_PARAMS(globalState));
+        DEBUG_COINCIDENCE_HEALTH(contourList, "expand3");
+        if (!coincidence->addExpanded(allocator  PATH_OPS_DEBUG_VALIDATE_PARAMS(globalState))) {
+            return false;
+        }
+        DEBUG_COINCIDENCE_HEALTH(contourList, "addExpanded2");
         coincidence->mark();
     }
+    DEBUG_COINCIDENCE_HEALTH(contourList, "missingCoincidence2");
     SkOpCoincidence overlaps;
     do {
         SkOpCoincidence* pairs = overlaps.isEmpty() ? coincidence : &overlaps;
         if (!pairs->apply()) {  // adjust the winding value to account for coincident edges
             return false;
         }
+        DEBUG_COINCIDENCE_HEALTH(contourList, "pairs->apply");
         // For each coincident pair that overlaps another, when the receivers (the 1st of the pair)
         // are different, construct a new pair to resolve their mutual span
         pairs->findOverlaps(&overlaps, allocator);
+        DEBUG_COINCIDENCE_HEALTH(contourList, "pairs->findOverlaps");
     } while (!overlaps.isEmpty());
     calcAngles(contourList, allocator);
     sortAngles(contourList);
     if (globalState->angleCoincidence()) {
         (void) missingCoincidence(contourList, coincidence, allocator);
         if (!coincidence->apply()) {
             return false;
         }
     }
 #if DEBUG_ACTIVE_SPANS
     coincidence->debugShowCoincidence();
     DebugShowActiveSpans(contourList);
 #endif
     return true;
 }