[Validator] smaller fixes for binary format
[Validator] no need to initialize properties with null
minor #11140 [Validator] smaller CS fixes (Tobion)

This PR was merged into the 2.3-dev branch.

Discussion
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[Validator] smaller CS fixes

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT

First commit fixes some CS of #11027
Second one removes `null` initialization from Validator as we don't do it.

Commits
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2025778 [Validator] no need to initialize properties with null
967576a [Validator] smaller fixes for binary format