tdb: commit 9b987e3923f7e8714acec6a2929435b1e6016645 from SAMBA

tdb: commit 9b987e3923f7e8714acec6a2929435b1e6016645 from SAMBA

Author: Volker Lendecke <vl@samba.org>
Date:   Tue Aug 12 22:31:52 2008 +0200

    Attempt to fix bug 5684

    With the ctdb checkin dde9f3f006 tdb optimized out write lock checks for
    write-enabled transaction. Sadly, this also removed the possibility to ever
    remove dead records left over from tdb_delete calls within a transaction.

    Tridge, please check this! Did dde9f3f006 have any reason beyond performance
    optimizations?

    Thanks,

    Volker
    (This used to be commit 3f884c4ae36f3260e63626bdd4989d9258ae6497)