8162546: change hidden options -Xdebug to --debug, -XshouldStop to --should-stop, and -diags to --diags
Reviewed-by: mcimadamore

8161020: javac, fold stop compilation options
Reviewed-by: mcimadamore

7060926: Attr.PostAttrAnalyzer misses a case
Reviewed-by: mcimadamore