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

tests/language_2/function_type/function_type88_test.dart

Index: tests/language_2/function_type/function_type88_test.dart
diff --git a/tests/language_2/function_type/function_type88_test.dart b/tests/language_2/function_type/function_type88_test.dart
index e693d08c2ea01fcff35ee8ff2d2b62e15a160ca4..0fbe70dbda22d68eff2187b18f4d406f7c261b59 100644
--- a/tests/language_2/function_type/function_type88_test.dart
+++ b/tests/language_2/function_type/function_type88_test.dart
@@ -264,10 +264,10 @@ class U88<T> {
       });
     }
     if (tIsInt || tIsBool) {
-      Expect.equals(true, m3 is F3<int>);
-      Expect.equals(true, m3 is F3<bool>);
-      Expect.equals(true, confuse(m3) is F3<int>);
-      Expect.equals(true, confuse(m3) is F3<bool>);
+      Expect.equals(tIsInt, m3 is F3<int>);
+      Expect.equals(tIsBool, m3 is F3<bool>);
+      Expect.equals(tIsInt, confuse(m3) is F3<int>);
+      Expect.equals(tIsBool, confuse(m3) is F3<bool>);
     }
   }