Revert change caused "Should pop, but ec not found in Vector" errors in ...

Reverted change caused "Should pop, but ec not found in Vector" errors in RestAPI.
- ERXApplication._endRequest() will call ERXEC.unlockAllContextsForCurrentThread() at proper time
- It's became to be possible to have unlocked ECs, not being disposed by this RouteController. It's causes unexpected side effects