Rename runAsync to scheduleMicrotask.

pkg/unittest/lib/unittest.dart

Index: pkg/unittest/lib/unittest.dart
diff --git a/pkg/unittest/lib/unittest.dart b/pkg/unittest/lib/unittest.dart
index 40408708603458500d7125b5ccabfed1ac083045..9eac4647ec9834a31401ad21a6d2f6f26df9d8ed 100644
--- a/pkg/unittest/lib/unittest.dart
+++ b/pkg/unittest/lib/unittest.dart
@@ -763,7 +763,7 @@ void _runTest() {
         _lastBreath = now;
         Timer.run(_nextTestCase);
       } else {
-        runAsync(_nextTestCase); // Schedule the next test.
+        scheduleMicrotask(_nextTestCase); // Schedule the next test.
       }
     });
   }
@@ -817,7 +817,7 @@ void _ensureInitialized(bool configAutoStart) {
   if (configAutoStart && _config.autoStart) {
     // Immediately queue the suite up. It will run after a timeout (i.e. after
     // main() has returned).
-    runAsync(runTests);
+    scheduleMicrotask(runTests);
   }
 }