Support X-Remote-User in web UI

radicale/web/internal_data/js/api/common.js

@@ -30,4 +30,21 @@ export function to_error_message(request) {
     }
 
     return request.status + " " + request.statusText;
+}
+
+/**
+ * @param {string} method
+ * @param {string} url
+ * @param {?string} user
+ * @param {?string} password
+ * @returns {XMLHttpRequest}
+ */
+export function create_request(method, url, user, password) {
+    let request = new XMLHttpRequest();
+    if (user !== null && password !== null) {
+        request.open(method, url, true, user, encodeURIComponent(password));
+    } else {
+        request.open(method, url, true);
+    }
+    return request;
 }