Include new constant for encryption status in the getter's javadoc

Added a bit more information in the javadocs about the new constant
ENCRYPTION_STATUS_ACTIVE_PER_USER in related methods/constants so
that developers don't miss checking for that constant when targeting
API Level 24.

Change-Id: Id9cd6248637fe0fc28d5161344abe02614b5f502
Fixes: 30073719
1 file changed