Fix #702 -- Fix U2F support in Firefox 57

src/pretix/static/pretixcontrol/js/ui/u2f-api.js

@@ -1,5 +1,5 @@
 //Copyright 2014-2015 Google Inc. All rights reserved.
-
+// Extended by Raphael Michel 2017 for compatibility with Firefox 57
 //Use of this source code is governed by a BSD-style
 //license that can be found in the LICENSE file or at
 //https://developers.google.com/open-source/licenses/bsd
@@ -10,6 +10,7 @@
 'use strict';
 
 
+var build_u2f_object = function () {
     /**
      * Namespace for the U2F api.
      * @type {Object}
@@ -47,7 +48,7 @@ u2f.MessageTypes = {
         'U2F_SIGN_REQUEST': 'u2f_sign_request',
         'U2F_SIGN_RESPONSE': 'u2f_sign_response',
         'U2F_GET_API_VERSION_REQUEST': 'u2f_get_api_version_request',
-    'U2F_GET_API_VERSION_RESPONSE': 'u2f_get_api_version_response'
+        'ndowsU2F_GET_API_VERSION_RESPONSE': 'u2f_get_api_version_response'
     };
 
 
@@ -470,7 +471,8 @@ u2f.WrappedAuthenticatorPort_.INTENT_URL_BASE_ =
      * @constructor
      * @private
      */
-u2f.WrappedIosPort_ = function() {};
+    u2f.WrappedIosPort_ = function () {
+    };
 
     /**
      * Launch the iOS client app request
@@ -746,3 +748,13 @@ u2f.getApiVersion = function(callback, opt_timeoutSeconds) {
             port.postMessage(req);
         });
     };
+
+    return u2f;
+};
+
+try {
+    var u2f = build_u2f_object();
+} catch (TypeError) {
+    // Firefox 57 sets the u2f object itself, we are not allowed to override it,
+    // so fail silently.
+}