Add assertTypes function

Author: sam-gc

packages-exp/auth-compat-exp/demo/public/common.js

@@ -27,15 +27,13 @@
 function initRecaptchaToggle(callback) {
   // Listen to recaptcha config togglers.
   var $recaptchaConfigTogglers = $('.toggleRecaptcha');
-  $recaptchaConfigTogglers.click(function(e) {
+  $recaptchaConfigTogglers.click(function (e) {
     // Remove currently active option.
     $recaptchaConfigTogglers.removeClass('active');
     // Set currently selected option.
     $(this).addClass('active');
     // Get the current reCAPTCHA setting label.
-    var size = $(e.target)
-      .text()
-      .toLowerCase();
+    var size = $(e.target).text().toLowerCase();
     callback(size);
   });
 }
@@ -44,11 +42,11 @@ function initRecaptchaToggle(callback) {
 if ('serviceWorker' in navigator) {
   navigator.serviceWorker
     .register('/service-worker.js', { scope: '/' })
-    .then(function(reg) {
+    .then(function (reg) {
       // Registration worked.
       console.log('Registration succeeded. Scope is ' + reg.scope);
     })
-    .catch(function(error) {
+    .catch(function (error) {
       // Registration failed.
       console.log('Registration failed with ' + error.message);
     });
@@ -61,7 +59,7 @@ if (window.Worker) {
    * Handles the incoming message from the web worker.
    * @param {!Object} e The message event received.
    */
-  webWorker.onmessage = function(e) {
+  webWorker.onmessage = function (e) {
     console.log('User data passed through web worker: ', e.data);
     switch (e.data.type) {
       case 'GET_USER_INFO':