Problem: Running CHECK TABLE ... FOR UPGRADE can be costly, so the
latest version in which this check had been performed used to be
cached in the .frm file so that repeated checks of already checked
tables were avoided. This version number was not stored in dd.tables
so this optimization was no longer possible with the new DD.

Solution: Add a new column last_checked_for_upgrade to dd.tables, and
use it to check if CHECK TABLE ... FOR UPGRADE has already been
performed for this version.

Change-Id: I89b81211eb6551dc809e4b311c8d8b4a7951580f