Show a spinner UI for zero-touch enrollment

chrome/browser/resources/chromeos/login/oobe_screen_oauth_enrollment.css

Index: chrome/browser/resources/chromeos/login/oobe_screen_oauth_enrollment.css
diff --git a/chrome/browser/resources/chromeos/login/oobe_screen_oauth_enrollment.css b/chrome/browser/resources/chromeos/login/oobe_screen_oauth_enrollment.css
index 19442dd42642d5bab366da8374bfd065a331eed6..ca00409379683f9ff2f4e812f711d3bbb1cfc6ae 100644
--- a/chrome/browser/resources/chromeos/login/oobe_screen_oauth_enrollment.css
+++ b/chrome/browser/resources/chromeos/login/oobe_screen_oauth_enrollment.css
@@ -23,6 +23,13 @@
   display: none;
 }
 
+.oauth-enroll-state-working #oauth-enroll-step-working {

[xiyuan, 2016/09/16 19:45:15]

Can we add class="fit" to the throbber-notice and put this into L33-35 and use
the style there?

[kumarniranjan, 2016/09/16 20:53:40]

Done.

+  display: block;
+  height: 50%;
+  margin-top: 50%;
+  width: 100%;
+}
+
 .oauth-enroll-state-error #oauth-enroll-step-error,
 .oauth-enroll-state-success #oauth-enroll-step-success,
 .oauth-enroll-state-abe-success #oauth-enroll-step-abe-success {
@@ -31,7 +38,6 @@
   margin: 0 auto;
 }
 
-.oauth-enroll-state-working #oauth-enroll-step-signin,
 .oauth-enroll-state-attribute-prompt-error
     #oauth-enroll-step-attribute-prompt-error,
 .oauth-enroll-state-signin #oauth-enroll-step-signin,
@@ -122,4 +128,3 @@
 #oauth-enrollment.saml #oauth-enroll-navigation {
   color: rgba(0, 0, 0, .54);
 }
-