flutter/engine#51393 introduced a new clause that was required for rendering TiledTextureContents because Snapshot was unable to capture the proper semantics to render it correctly. Specifically in that case the geometry has been expanded. The way TileTextureContents works when rendering without the Snapshot optimization is that expanding the geometry should be counteracted by the texcoords, as per the effect transform math. There is no way to represent this with the Snapshot. This means we need to have some concept of the "source rect" or another matrix to capture the difference between vertices and texcoords.

I'm not sure if there are other places in the code where this would be beneficial but not having it forces us to have a render pass when we don't need one.

cc @jonahwilliams