Add sk_parallel_for()

tests/PathOpsThreadedCommon.cpp

Index: tests/PathOpsThreadedCommon.cpp
diff --git a/tests/PathOpsThreadedCommon.cpp b/tests/PathOpsThreadedCommon.cpp
index 0adde915e0870fbbea6205b80f477e6cf82f9578..10501d139c42f5cd1eca743e0b1230f76fa2df4b 100644
--- a/tests/PathOpsThreadedCommon.cpp
+++ b/tests/PathOpsThreadedCommon.cpp
@@ -16,8 +16,7 @@ PathOpsThreadedTestRunner::~PathOpsThreadedTestRunner() {
 }
 
 void PathOpsThreadedTestRunner::render() {
-    SkTaskGroup tg;
-    for (int index = 0; index < fRunnables.count(); ++ index) {
-        tg.add(fRunnables[index]);
-    }
+    sk_parallel_for(fRunnables.count(), [&](int i) {
+        fRunnables[i]->run();
+    });
 }