Revert "Allow AID_MEDIA to capture layer for video thumbnails"

This reverts commit da6c1596.

Reason for revert: since we're reworking the solution to move
the use of renderengine to mediaserver side, this permission
is no longer needed.

bug: 140894732
bug: 135717526
Change-Id: Ib3b313c2673e9d5a26104f0719cc81f9632ed934