* #20833: layer brush doesn't work with multires. * #20946: sculpt mode partially removes parts of the mesh in the viewport. * #20420: grab brush stops after moving some distance. * #20906: sculpt grab tool moves in wrong direction. * #21132 and #21272: undo on object with subdivision surface modifier crashes. * #21115: subsurf + multires + sculpting + undo causes crash. * #20683: sculpt + multires apply + undo crash. * #19094: wrong outline in solid mode.