RFR: JDK-8223038: JPackage code signing fails on Mac.

[semyon.sadetsky at oracle.com]

bug: https://bugs.openjdk.java.net/browse/JDK-8223038

webrev: http://cr.openjdk.java.net/~ssadetsky/8223038/webrev.00/

This is a regression of 8219683 where Java runtime was moved out from 
PlugIns which made codesign unable to detect the bundle type. The fix 
points codesign to the valid path it can recognize and sign accordingly.

--Semyon