java install shouldn't delete /usr/bin !

Now you have to set a flag AND change the default install dir to
make it try.

Change-Id: Ib0b063d7419c86f5f4e1a59bb2f030eb0c54dc4e
Merge topic '14833-install-shouldnt-rm-usr-bin' into master

87ceeeae java install shouldn't delete /usr/bin !