Fix warnings that were exposed when running with SK_DEBUG enable on an optimized release build.

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 95 matching lines @@
         if (sortable) {
             segment = angle->segment();
             sumWinding = segment->updateWindingReverse(angle);
         }
         SkOpSegment* first = nullptr;
         const SkOpAngle* firstAngle = angle;
         while ((angle = angle->next()) != firstAngle) {
             segment = angle->segment();
             SkOpSpanBase* start = angle->start();
             SkOpSpanBase* end = angle->end();
-            int maxWinding;
+            int maxWinding SK_INIT_TO_AVOID_WARNING;
             if (sortable) {
                 segment->setUpWinding(start, end, &maxWinding, &sumWinding);
             }
             if (!segment->done(angle)) {
                 if (!first && (sortable || start->starter(end)->windSum() != SK_MinS32)) {
                     first = segment;
                     *startPtr = start;
                     *endPtr = end;
                 }
                 // OPTIMIZATION: should this also add to the chase?
@@ skipping 402 matching lines @@
         if (!coincidence->apply()) {
             return false;
         }
     }
 #if DEBUG_ACTIVE_SPANS
     coincidence->debugShowCoincidence();
     DebugShowActiveSpans(contourList);
 #endif
     return true;
 }