pub fn register_listing_theme_elements(
reg: &dyn ThemeRegistry,
owner: ElementOwner,
)Expand description
Register every listing.* element under owner. Idempotent by
name, so re-activation on a second listing buffer is free.
Separate from DirectoryListingMode::on_activate so tests (and
the theme introspection surfaces) can register the vocabulary
without standing up a mode context.