Function jsonrpc_http_server::cors::get_cors_allow_headers

pub fn get_cors_allow_headers<T, O, F>(
    headers: impl Iterator<Item = T>, 
    requested_headers: impl Iterator<Item = T>, 
    cors_allow_headers: &AccessControlAllowHeaders, 
    to_result: F
) -> AllowCors<Vec<O>> where
    F: Fn(T) -> O,
    T: AsRef<str>, 

Validates if the AccessControlAllowedHeaders in the request are allowed.