The array SecureVmArgPrefixes in deploy/src/javaws/share/native/secure.c contains "-XX:PermSize" and "-XX:MaxPermSize" which are both removed in JDK 8.

While looking at this it might also be worth looking into JEP 173: Retire Some Rarely-Used GC Combinations. There are flags in secure.c that may become deprecated by this project as well. (-Xincgc for instance)