@goderbauer Since the PR has been open for a while, is this waiting for anything from me? (Besides the merge conflict.)

Sorry for the delay.

Is the reasoning here that we can remove the check because in an NNBD world List<Widget> children can never contain null? We've left these kind of null checks in the code base for now because not all apps have migrated to NNBD yet and they still need these asserts for proper error reporting.

This pull request executed golden file tests, but it has not been updated in a while (20+ days). Test results from Gold expire after as many days, so this pull request will need to be updated with a fresh commit in order to get results from Gold.

For more guidance, visit Writing a golden file test for package:flutter.

Reviewers: Read the Tree Hygiene page and make sure this patch meets those guidelines before LGTMing.

Sorry for the delay.

Is the reasoning here that we can remove the check because in an NNBD world List<Widget> children can never contain null? We've left these kind of null checks in the code base for now because not all apps have migrated to NNBD yet and they still need these asserts for proper error reporting.

For how long will this be the case ?.
That some people dont fix their codebase to be NNBD but still expect to function in the otherwise evolving flutter versions is to prevent flutter itself to be pure NNBD.
Why not simple dictate that after version X, its pure NNBD, people who refusee to adapt are stuck on earlier version.

Is there any update on this? Having const available for rows, columns, stacks, containers and much more would be a huge lift

Done! See #118837

Thanks ! today is a good day :)

It'll still requires a little more work before it is truly done, but we're on it.