Add css $classes variable to the OldChangesListRecentChangesLine hook

- will update LiquidThreads accordingly and do not see
this hook used in any other extension in Wikimedia git repos.

Change-Id: Ib8f297b39dbd5fba980bb0d4773d0e01f2b922f4
Merge "Add css $classes variable to the OldChangesListRecentChangesLine hook"