Revert "fix #30462, update function_type tests to understand covariant generics"

tests/language_2/function_type/function_type0_test.dart

Index: tests/language_2/function_type/function_type0_test.dart
diff --git a/tests/language_2/function_type/function_type0_test.dart b/tests/language_2/function_type/function_type0_test.dart
index f01e0208bd8dbdb687c50bb33e519716a402d1ee..4391b6643a6643d7651cee02a4a76b662af9e4f6 100644
--- a/tests/language_2/function_type/function_type0_test.dart
+++ b/tests/language_2/function_type/function_type0_test.dart
@@ -221,10 +221,10 @@ class U0<T> {
       });
     }
     if (tIsInt || tIsBool) {
-      Expect.equals(true, m1 is F1<int>);
-      Expect.equals(true, m1 is F1<bool>);
-      Expect.equals(true, confuse(m1) is F1<int>);
-      Expect.equals(true, confuse(m1) is F1<bool>);
+      Expect.equals(tIsInt, m1 is F1<int>);
+      Expect.equals(tIsBool, m1 is F1<bool>);
+      Expect.equals(tIsInt, confuse(m1) is F1<int>);
+      Expect.equals(tIsBool, confuse(m1) is F1<bool>);
     }
   }