Bottom of liquids are not rendered from above

Likely relates to MC-34751 (recommending change of resolution from Closed to Resolved).

The bug

Despite having internal top and side faces, fluids do not render their bottom faces at all, even though they should.

A leftover bug from 1.7's changes - MC-35658 added back the top face and MC-40621 the side faces, but the bottom face remains absent despite existing beforehand.

How to fix

Could be fixed by making fluids use models like items and blocks do.