Separate the demo user factory reset option with admin user factory reset option.

A security vulnerability was discovered by Android security. b/292548775 Within a short period of time after the device reboot, the user could enter the settings page and factory reset the device. Android Enterprise suggests to add DISALLOW_FACTORY_RESET user restriction to the device.

However, DISALLOW_FACTORY_RESET will be enabled on all Android users, including both the admin user and the demo user. The existing behavior in Android settings is that once the user restriction is set, factory reset button will be greyed out, which makes the factory reset functionality in demo user go away.

In demo user, the factory reset command will be forwarded to the current active device owner. So in this change, we separate the button for admin user and the button for demo user.

In demo user, the button is still visible when the restriction is set.

And in admin user, the button will be greyed out as expected.

Once this change is in, then Pixel Retail Demo could set the user restriction properly and rely on its internal logic to do factory reset. If other applications are trying to do the factory reset, it will be denied by OS.

BUG: 292548775
Change-Id: I9d2d47bb29bc2c1e05058b246908768cd2f95990