Once priority estimation was removed, not all transactions in the mempool are tracked in the fee estimation mempool tracking (have an entry in mapMemPoolTxs). So there is no error if a transaction is not found for removal.
This will eliminate these incorrect lines from debug.log:
2016-11-06 07:19:18.724305 Blockpolicy error mempool tx 93100e69a817a6b2034456ad3127124f63b9a89d71704ed11d584d5db5fefc54 not found for removeTx