Function generate_js_source_map

pub fn generate_js_source_map<'a>(
    files_map: &impl Files,
    mappings: Vec<(BytePos, LineCol)>,
    original_source_maps: impl IntoIterator<Item = &'a Rope>,
    original_source_maps_complete: bool,
    inline_sources_content: bool,
) -> Result<Rope>

original_source_maps_complete indicates whether the original_source_maps cover the whole map, i.e. whether every module that ended up in mappings had an original sourcemap.