anchor.diff:  foo(x) => 1;
   var v = const A(foo);''');
       await computeAnalysisResult(source);
  -    assertNoErrors(source);
  +    assertErrors(source, [StaticWarningCode.ARGUMENT_TYPE_NOT_ASSIGNABLE]);
       verify([source]);
     }
   
  
positive.code: 
  @reflectiveTest
  class CheckedModeCompileTimeErrorCodeTest extends ResolverTestCase {
    test_fieldFormalParameterAssignableToField_extends() async {
      // According to checked-mode type checking rules, a value of type B is
      // assignable to a field of type A, because B extends A (and hence is a
  
negative.code:   final B b;
    const C(this.b);
  }
  const A u = const A();
  var v = const C(u);''');
      await computeAnalysisResult(source);
      assertErrors(source, [
        CheckedModeCompileTimeErrorCode.CONST_CONSTRUCTOR_PARAM_TYPE_MISMATCH
  