pkg/front_end/testcases/inference/void_return_type_subtypes_dynamic.dart:29:5: Context: Write to x@543
  x = 123;
    ^
pkg/front_end/testcases/inference/void_return_type_subtypes_dynamic.dart:30:5: Context: Write to x@543
  x = 'hi';
    ^
pkg/front_end/testcases/inference/void_return_type_subtypes_dynamic.dart:31:5: Context: Write to y@598
  y = /*error:INVALID_ASSIGNMENT*/ 123;
    ^
pkg/front_end/testcases/inference/void_return_type_subtypes_dynamic.dart:32:5: Context: Write to y@598
  y = /*error:INVALID_ASSIGNMENT*/ 'hi';
    ^