Hide "Add user" button when enrollment screen is active.

chrome/browser/resources/chromeos/login/header_bar.js

Index: chrome/browser/resources/chromeos/login/header_bar.js
diff --git a/chrome/browser/resources/chromeos/login/header_bar.js b/chrome/browser/resources/chromeos/login/header_bar.js
index abfba3c28470d1a61064beaa9dd099ddb3f054a4..0763c3446d25c7041a152915163e0b3c9c200081 100644
--- a/chrome/browser/resources/chromeos/login/header_bar.js
+++ b/chrome/browser/resources/chromeos/login/header_bar.js
@@ -312,6 +312,8 @@ cr.define('login', function() {
      */
     updateUI_: function() {
       var gaiaIsActive = (this.signinUIState_ == SIGNIN_UI_STATE.GAIA_SIGNIN);
+      var enrollmentIsActive =
+          (this.signinUIState_ == SIGNIN_UI_STATE.ENROLLMENT);
       var accountPickerIsActive =
           (this.signinUIState_ == SIGNIN_UI_STATE.ACCOUNT_PICKER);
       var supervisedUserCreationDialogIsActive =
@@ -340,6 +342,7 @@ cr.define('login', function() {
       $('add-user-button').hidden =
           (!this.isNewGaiaFlow_ && !accountPickerIsActive) ||
           (this.isNewGaiaFlow_ && gaiaIsActive) ||
+          enrollmentIsActive ||
           isMultiProfilesUI ||
           isLockScreen ||
           supervisedUserCreationDialogIsActiveAndNotIntro;