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

tests/language_2/function_type/function_type20_test.dart

Index: tests/language_2/function_type/function_type20_test.dart
diff --git a/tests/language_2/function_type/function_type20_test.dart b/tests/language_2/function_type/function_type20_test.dart
index 309f5549fedfb50bf9f134471182fb3180a1628b..47c17a138fb22cc84917a925446b967eacc12358 100644
--- a/tests/language_2/function_type/function_type20_test.dart
+++ b/tests/language_2/function_type/function_type20_test.dart
@@ -244,10 +244,10 @@ class U20<T> {
       });
     }
     if (tIsInt || tIsBool) {
-      Expect.equals(true, m2 is F2<int>);
-      Expect.equals(true, m2 is F2<bool>);
-      Expect.equals(true, confuse(m2) is F2<int>);
-      Expect.equals(true, confuse(m2) is F2<bool>);
+      Expect.equals(tIsInt, m2 is F2<int>);
+      Expect.equals(tIsBool, m2 is F2<bool>);
+      Expect.equals(tIsInt, confuse(m2) is F2<int>);
+      Expect.equals(tIsBool, confuse(m2) is F2<bool>);
     }
   }
 
@@ -317,10 +317,10 @@ class U20<T> {
       });
     }
     if (tIsInt || tIsBool) {
-      Expect.equals(true, m4 is F4<int>);
-      Expect.equals(true, m4 is F4<bool>);
-      Expect.equals(true, confuse(m4) is F4<int>);
-      Expect.equals(true, confuse(m4) is F4<bool>);
+      Expect.equals(tIsInt, m4 is F4<int>);
+      Expect.equals(tIsBool, m4 is F4<bool>);
+      Expect.equals(tIsInt, confuse(m4) is F4<int>);
+      Expect.equals(tIsBool, confuse(m4) is F4<bool>);
     }
   }