refactor: debugElement.query is nullable

[lacolaco]

This is a necessary step to pass CI for angular/angular#32365

DebugElement.query can return null in fact but its type definition doesn't include it.

[mmalerba]

Looks like lint check is failing because some lines are too long now, otherwise LGTM

[lacolaco]

@mmalerba How can I format those files? yarn format didn't work.

[mmalerba]

I don't think we ever fully switched to using clang format because we were afraid of causing rebase issues with every open PR. Sadly, the best way is probably just to fix them by hand

[angular-automatic-lock-bot]

This issue has been automatically locked due to inactivity.
Please file a new issue if you are encountering a similar or related problem.

Read more about our automatic conversation locking policy.

_{This action has been performed automatically by a bot.}