harden and speed up path op unit tests

tests/PathOpsDQuadTest.cpp

Index: tests/PathOpsDQuadTest.cpp
diff --git a/tests/PathOpsDQuadTest.cpp b/tests/PathOpsDQuadTest.cpp
index 89da6592668ad804e171a919b0ec4a1c527f01cd..5921b695782398911abef0ad0eb142e034c5162f 100644
--- a/tests/PathOpsDQuadTest.cpp
+++ b/tests/PathOpsDQuadTest.cpp
@@ -4,6 +4,7 @@
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
+#include "PathOpsTestCommon.h"
 #include "SkPathOpsQuad.h"
 #include "Test.h"
 
@@ -36,6 +37,7 @@ static const size_t tests_count = SK_ARRAY_COUNT(tests);
 static void PathOpsDQuadTest(skiatest::Reporter* reporter) {
     for (size_t index = 0; index < tests_count; ++index) {
         const SkDQuad& quad = tests[index];
+        SkASSERT(ValidQuad(quad));
         bool result = quad.pointInHull(inPoint[index]);
         if (!result) {
             SkDebugf("%s [%d] expected in hull\n", __FUNCTION__, index);