In the `FileList` struct, rename the `AssetLibraryReference *asset_library` field to `asset_library_ref` -- it's a description of which asset library is used, and not the asset library itself. This is to make space for a future `AssetLibrary *asset_library` field, which will point to an actual asset library struct/class. No functional changes. Reviewed by: Severin Differential Revision: https://developer.blender.org/D12151