look for deleted pts when detecting line/curve coincident edges

tests/PathOpsSimplifyTest.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 "PathOpsExtendedTest.h"
 
 #define TEST(name) { name, #name }
 
@@ skipping 4741 matching lines @@
     testSimplify(reporter, path, filename);
 }
 
 static void testArc(skiatest::Reporter* reporter,const char* filename) {
     SkRect r = SkRect::MakeWH(150, 100);
     SkPath path;
     path.arcTo(r, 0, 0.0025f, false);
     testSimplify(reporter, path, filename);
 }
 
+static void testIssue3838(skiatest::Reporter* reporter,const char* filename) {
+    SkPath path;
+    path.moveTo(220, 170);
+    path.lineTo(200, 170);
+    path.lineTo(200, 190);
+    path.lineTo(180, 190);
+    path.lineTo(180, 210);
+    path.lineTo(200, 210);
+    path.lineTo(200, 250);
+    path.lineTo(260, 250);
+    path.lineTo(260, 190);
+    path.lineTo(220, 190);
+    path.lineTo(220, 170);
+    path.close();
+    path.moveTo(220, 210);
+    path.lineTo(220, 230);
+    path.lineTo(240, 230);
+    path.lineTo(240, 210);
+    path.lineTo(220, 210);
+    path.close();
+    testSimplify(reporter, path, filename);
+}
+
 static void (*skipTest)(skiatest::Reporter* , const char* filename) = 0;
 static void (*firstTest)(skiatest::Reporter* , const char* filename) = 0;
 static void (*stopTest)(skiatest::Reporter* , const char* filename) = 0;
 
 static TestDesc tests[] = {
+    TEST(testIssue3838),
     TEST(testArc),
     TEST(testTriangle2),
     TEST(testTriangle1),
     TEST(testQuads64),
     TEST(testQuads63),
     TEST(testQuads62),
     TEST(testRect4),
     TEST(testRect3),
     TEST(testQuadralateral10),
     TEST(testQuads61),
@@ skipping 426 matching lines @@
 
 DEF_TEST(PathOpsSimplify, reporter) {
     if (runSubTests && runSubTestsFirst) {
         RunTestSet(reporter, subTests, subTestCount, firstSubTest, NULL, stopTest, runReverse);
     }
     RunTestSet(reporter, tests, testCount, firstTest, skipTest, stopTest, runReverse);
     if (runSubTests && !runSubTestsFirst) {
         RunTestSet(reporter, subTests, subTestCount, firstSubTest, NULL, stopTest, runReverse);
     }
 }