fixed ethcore tx_filter

[debris]

• TransactionFilter was never added as ChainNotify
• therefore cache was never cleared
• this could lead to incorrect permissions being granted

a simplest solution is to remove a cache at all, cause it would be cleared on every block anyway use lru_cache instead of manually cleaning the cache

[tomusdrw]

This is pretty hot code during transaction import (note we are checking EVERY transaction), imho cache would make sense here. Why not add it to ChainNotify?

[debris]

This is pretty hot code during transaction import (note we are checking EVERY transaction), imho cache would make sense here

You are right. I looked at the code again and actually not cleaning the cache does not lead to incorrect behaviour. Cache just becomes useless.

Why not add it to ChainNotify?

I want to get rid of ChainNotify

I updated the pr. Replaced HashMap with LruCache

[debris]

cc @andresilva @tomusdrw

[andresilva]

LGTM!