Probably nice for the people that contributed to 9.0 to see themselves in the AUTHORS file :)

This commit consists of patches automatically generated for this project on https://scrutinizer-ci.com

* DI
* Tests
* moved OC_SubAdmin to legacy
* Added to private OC\GroupManager

This is a string

This reverts commit 6a1a4880.

2. use count instead of sizeof. Latter is an alias to first one, practically we stick to count everywhere. Having it consistent helps with readability.
3. move whitespace so we have $groupUsers[] = $filteredUser; instead of $groupUsers []= $filteredUser;

Fix #9972

removed cachedUserGroupIds, instead changed indexing in getUserGroups to groupId

clean up of function getUserGroupIds and improved caching mechanism of cachedUserGroupIds

defined $uid in getUserGroupIds