pkg/unittest: much cleaner support for arbitrary args in expectAsync functions

pkg/unittest/test/unittest_test_returning_future_using_runasync_test.dart

Index: pkg/unittest/test/unittest_test_returning_future_using_runasync_test.dart
diff --git a/pkg/unittest/test/unittest_test_returning_future_using_runasync_test.dart b/pkg/unittest/test/unittest_test_returning_future_using_runasync_test.dart
index 98f276b825f04a9d3b8d856f1266f0ea612247b4..e5fc304d7168b80a52c06d0f9512f35a1f5d14f2 100644
--- a/pkg/unittest/test/unittest_test_returning_future_using_runasync_test.dart
+++ b/pkg/unittest/test/unittest_test_returning_future_using_runasync_test.dart
@@ -15,58 +15,48 @@ var testFunction = (_) {
   test("successful", () {
     return _defer(() {
       scheduleMicrotask(() {
-        guardAsync(() {
-          expect(true, true);
-        });
+        expect(true, true);
       });
     });
   });
   test("fail1", () {
-    var callback = expectAsync0((){});
+    var callback = expectAsync(() {});
     return _defer(() {
       scheduleMicrotask(() {
-        guardAsync(() {
-          expect(true, false);
-          callback();
-        });
+        expect(true, false);
+        callback();
       });
     });
   });
   test('error1', () {
-    var callback = expectAsync0((){});
-    var excesscallback = expectAsync0((){});
+    var callback = expectAsync(() {});
+    var excesscallback = expectAsync(() {});
     return _defer(() {
       scheduleMicrotask(() {
-        guardAsync(() {
-          excesscallback();
-          excesscallback();
-          callback();
-        });
+        excesscallback();
+        excesscallback();
+        callback();
       });
     });
   });
   test("fail2", () {
-    var callback = expectAsync0((){});
+    var callback = expectAsync(() {});
     return _defer(() {
       scheduleMicrotask(() {
-        guardAsync(() {
-          fail('failure');
-          callback();
-        });
+        fail('failure');
+        callback();
       });
     });
   });
   test('error2', () {
-    var callback = expectAsync0((){});
-    var excesscallback = expectAsync0((){});
+    var callback = expectAsync(() {});
+    var excesscallback = expectAsync(() {});
     return _defer(() {
       scheduleMicrotask(() {
-        guardAsync(() {
-          excesscallback();
-          excesscallback();
-          excesscallback();
-          callback();
-        });
+        excesscallback();
+        excesscallback();
+        excesscallback();
+        callback();
       });
     });
   });