pkg:compiler - enable and fix null operator lints

Change-Id: I5aaef20fdd61fd6ac9dc69978111fb680c7f99e5
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/211624
Auto-Submit: Kevin Moore <kevmoo@google.com>
Commit-Queue: Kevin Moore <kevmoo@google.com>
Reviewed-by: Joshua Litt <joshualitt@google.com>

https://dart.googlesource.com/sdk/+/b85488cedd0a21f201a9e8b768e94ca182de0b7e
1 file changed
tree: 9cbdfb785ff22a6bdb372ccf187c6ef79cc07994
  1. commits.json