Removed unused legacy logic from AssetAdmin
Removed unused legacy logic from AssetAdmin

open-sausages/silverstripe-asset-admin,open-sausages/silverstripe-asset-admin,open-sausages/silverstripe-assets-gallery,silverstripe/silverstripe-asset-admin,silverstripe/silverstripe-asset-admin,open-sausages/silverstripe-assets-gallery