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

tests/language_2/function_type/function_type48_test.dart

Index: tests/language_2/function_type/function_type48_test.dart
diff --git a/tests/language_2/function_type/function_type48_test.dart b/tests/language_2/function_type/function_type48_test.dart
index 93da37a56858b8c2e3fb50058026d43588f291a0..21b247bfc9d0e6bfa0482006414cc47271299354 100644
--- a/tests/language_2/function_type/function_type48_test.dart
+++ b/tests/language_2/function_type/function_type48_test.dart
@@ -197,10 +197,10 @@ class U48<T> {
       });
     }
     if (tIsInt || tIsBool) {
-      Expect.equals(true, m0 is F0<int>);
-      Expect.equals(true, m0 is F0<bool>);
-      Expect.equals(true, confuse(m0) is F0<int>);
-      Expect.equals(true, confuse(m0) is F0<bool>);
+      Expect.equals(tIsInt, m0 is F0<int>);
+      Expect.equals(tIsBool, m0 is F0<bool>);
+      Expect.equals(tIsInt, confuse(m0) is F0<int>);
+      Expect.equals(tIsBool, confuse(m0) is F0<bool>);
     }
   }