The biggest thing you have to worry about is the Criminal History Records Check (CHRC).
When a juvenile has been tried as an adult, then the criminal record is applicable. Otherwise, juvenile records should not be considered for purposes of the criminal history records check statute.
This is from the TSA office of Chief Counsel and is provided to airline and airport badging people who are responsible for adjudicating "hits" that are returned during the FBI background check.
From an HR perspective, how they would look upon this is hit or miss and will probably vary from airline to airline. If they look at it fairly, they would have to ask themselves who hasn't shoplifted when they were a kid.