topic: drop topicfilter usage from topicrepo.commitctx() This block of code was introduced in 13313d0cab71, but the commit description doesn't explain the exact intent of this code. The fact that the result of other.commitctx() was discarded makes me think that this block only existed to deal with amends, and it was only useful for code that was removed earlier in this series. The only code that's left in commitctx() is adding current topic to workingcommitctx, and I don't think we need to adjust repo filter for that.