Made $map protected and moved it to construct.

By making $map protected and moving it to the construct, you can simply extend the BasicPermissionMap class if you want to simply add some extra permissions. In it's current form, you have to copy/paste the entire array AND the getMasks and contains functions. 
merged branch Brammm/master (PR #7601)

This PR was merged into the master branch.

Discussion
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[Security] [Acl] [BasicPermissionMap] Made $map protected and moved it to __construct

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

By making $map protected and moving it to the construct, you can simply extend the BasicPermissionMap class if you want to simply add some extra permissions. In it's current form, you have to copy/paste the entire array AND the getMasks and contains functions. 

Commits
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1369d54 Made $map protected and moved it to construct.