Add more OWNERS to DefaultPermissionGrantPolicy

All changes to DPGP are required by gerrit to be reviewed by one of the owners
Some of the changes are simple enough that the blocks this causes is
not worth it

This change must be submitted through aosp

Test: test later in gerrit
Change-Id: I8d066a403376c7e620664abda1dbb71d9c87bb04
1 file changed