Function azul_core::app_resources::add_fonts_and_images

pub fn add_fonts_and_images<U: FontImageApi>(
    app_resources: &mut AppResources, 
    render_api: &mut U, 
    pipeline_id: &PipelineId, 
    display_list: &DisplayList, 
    node_data: &NodeDataContainer<NodeData>, 
    load_font_fn: LoadFontFn, 
    load_image_fn: LoadImageFn
)

Scans the DisplayList for new images and fonts. After this call, the RenderApi is guaranteed to know about all FontKeys and FontInstanceKey