only update the values which really changed
get the correct owner path for part files
Merge pull request #8412 from owncloud/sharing_fix_part_file_rename

[sharing] fix rename of part files
return the new name if a mount point was renamed
[tx-robot] updated from transifex
Merge pull request #8415 from owncloud/sharing_fix_rename

[sharing] return the new name if a mount point was renamed
[tx-robot] updated from transifex