Injection camera: Block camera access on devices that don't support injection camera

- For devices that do not support camera injection, the external camera
ID will not be registered in the camera service. In this case, when the
user uses the camera on the virtual display of the second device (such
as a Chromebook, tablet) connected by the device, the internal camera
will be projected onto the virtual display. In order not to display the
internal camera screen on the virtual display to protect personal
privacy on the device, onCameraUnavailable will be called.

Bug: 207481642
Test: Manual
Change-Id: Iea12915734373e9f3a5d0c03874cf49236acc3f5