Show current domain on "add user" page.

While the original domain name remains unchanged after domain rename,
the new name is provided as "displayDomain" and should be shown in UI.

BUG=b/67784447

Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: I7e083f31ca2492fd6c32d401a024e4da4b54794e
Reviewed-on: https://chromium-review.googlesource.com/1038503
Commit-Queue: Sergey Poromov <poromov@chromium.org>
Reviewed-by: Alexander Alekseev <alemate@chromium.org>
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#555444}

chrome/browser/resources/gaia_auth_host/authenticator.js

@@ -79,6 +79,7 @@ cr.define('cr.login', function() {
                      // not called before dispatching |authCopleted|.
                      // Default is |true|.
     'flow',          // One of 'default', 'enterprise', or 'theftprotection'.
+    'enterpriseDisplayDomain',     // Current domain name to be displayed.
     'enterpriseEnrollmentDomain',  // Domain in which hosting device is (or
                                    // should be) enrolled.
     'emailDomain',                 // Value used to prefill domain for email.
@@ -359,9 +360,8 @@ cr.define('cr.login', function() {
         url = appendParam(url, 'chrometype', data.chromeType);
       if (data.clientId)
         url = appendParam(url, 'client_id', data.clientId);
-      if (data.enterpriseEnrollmentDomain)
-        url =
-            appendParam(url, 'manageddomain', data.enterpriseEnrollmentDomain);
+      if (data.enterpriseDisplayDomain)
+        url = appendParam(url, 'manageddomain', data.enterpriseDisplayDomain);
       if (data.clientVersion)
         url = appendParam(url, 'client_version', data.clientVersion);
       if (data.platformVersion)