Grids: make option goAutoAddRows also work with Tab key.
Also don't loose the state of FRowAutoInserted in KeyDown() when user presses Crl,Alt,Shift or Meta key
(otherwise "undoing" an auto-added row doesn't work anymore)


git-svn-id: http://svn.freepascal.org/svn/lazarus/trunk@39864 4005530d-fff6-0310-9dd1-cebe43e6787f