Remove unsafe uses of TypeImpl.withNullability (use TypeSystem instead).

Change-Id: I5df47ca582aa5583055d3700668de992676bc42a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/103541
Reviewed-by: Konstantin Shcheglov <scheglov@google.com>
Commit-Queue: Paul Berry <paulberry@google.com>

https://dart.googlesource.com/sdk/+/22c086fbe56102e304197c1d52fbd92d0efcb1f0
1 file changed
tree: fe6d28ab98b92f4ac81f88935cd5ee7b243168d3
  1. commits.json