Fix test which assumes `toString` of `NullThrownError()`. (#1721)
The `NullThrownError` is deprecated.
It should not be possible to have it thrown by null safe Dart, and the type is being replaced by a `TypeError` in general.
A test here assumes that the `toString` of a `NullThrownError` is `Instance of 'NullThrownError'`, where it's now `Instance of 'TypeError'`.
In general, we do not promise that `toString` of error objects are stable. (Our breaking-change rules do not promise to not break programs which depend on specific `Error`s being thrown.)
2 files changed