Function handle_find_shadow_elements_css_selector

pub(crate) fn handle_find_shadow_elements_css_selector(
    documents: &DocumentCollection,
    pipeline: PipelineId,
    shadow_root_id: String,
    selector: String,
    reply: IpcSender<Result<Vec<String>, ErrorStatus>>,
)

https://w3c.github.io/webdriver/#find-elements-from-shadow-root