lock_release_try(): Implement innodb_evict_tables_on_commit_debug.
Before releasing any locks, collect the identifiers of tables to
be evicted. After releasing all locks, look up for the tables and
evict them if it is safe to do so.

trx_t::commit_tables(): Remove the eviction logic.

trx_t::commit_in_memory(): Invoke release_locks() only after
commit_tables().