Make location enabled check configurable when returning scan results.

Some device classes (e.g. Wear) don't allow location to be enabled but
would still like to allow LE scanning to take place. This patch allows
the location enabled check to be bypassed if the platform is so configured.
Even if the location check is disabled, the calling app must still have
one of the location permissions.

Bug: 21852542
Change-Id: I206366ce262776d4668c0c42e066f0e20f5fdfeb