Julian Eisel
3fc9fc1cb4
It's useful to easily see which data-blocks are assets and which not. So just like we usually show the library linking/override icons, we show the asset icon there (these are mutually exclusive data-block states). Uses the `'MAT_SPHERE_SKY` icon, which wasn't used before (except by an add-on!) and is sorta fitting, but not quite. We should either change this one or add an own asset icon. Meanwhile this isn't too bad :) Also adds an internal macro to check if a data-block is an asset, consistent to how we do it for libraries and library overrides.