Fix crash if try and select -10000 in a menu item (reported by magmar452):
http://chdk.setepontos.com/index.php?topic=11550.msg119003#msg119003
Define CAM_IS_VID_REC_WORKS for models tested by koshy.
http://chdk.setepontos.com/index.php?topic=9986.msg118975#msg118975