Refactored error screen logic.

chrome/app/chromeos_strings.grdp

 <?xml version="1.0" encoding="utf-8"?>
 <!-- ChromeOS-specific strings (included from generated_resources.grd).
      Everything in this file is wrapped in <if expr="pp_ifdef('chromeos')">. -->
 <grit-part>
   <!-- Idle Logout Dialog Strings -->
   <message name="IDS_IDLE_LOGOUT_TITLE" desc="Dialog title for the idle logout dialog">
     Are you still there?
   </message>
   <message name="IDS_IDLE_LOGOUT_WARNING_RESTART" desc="Restart label for the idle logout dialog">
     This computer will reset in <ph name="LOGOUT_TIME_LEFT">$1<ex>20</ex></ph> seconds.
@@ skipping 3498 matching lines @@
     contact your network administrator to make sure the proxy
     server is working. If you don't believe you should be using a
     proxy server, adjust your <ph name="LINK_START">$1<ex>&gt;a&lt;</ex></ph>proxy settings<ph name="LINK_END">$2<ex>&gt;/a&lt;</ex></ph>.
   </message>
   <message name="IDS_LOGIN_MAYBE_CAPTIVE_PORTAL_NETWORK_SELECT" desc="An offline message shown when we suggest that user may select other network.">
     You may also select another network.
   </message>
   <message name="IDS_LOGIN_ERROR_CAPTIVE_PORTAL_NO_GUEST_MODE" desc="An error message shown when we suggest that user may be behind the captive portal but Guest mode is disabled.">
     Your password cannot be verified on this current network. Please select another network.
   </message>
+  <message name="IDS_LOGIN_TIMEOUT_TITLE" desc="An offline message title shown when Gaia frame loading is timed out.">
+    Gaia loading timeout
+  </message>
   <message name="IDS_NOTIFICATION_PANEL_TITLE" desc="Text for the title of the notification panel.">
     Notifications
   </message>
   <message name="IDS_LOGIN_OFFLINE_TITLE" desc="Title of an offline message that shows up in OOBE sign-in screen.">
     You are currently offline
   </message>
   <message name="IDS_LOGIN_OFFLINE_MESSAGE" desc="An offline message that shows up in OOBE sign-in screen.">
     Please connect to the Internet to signin into your Chromebook.
   </message>
   <message name="IDS_GUEST" desc="Shown in login panel for users that would like to browse without signing in.">
@@ skipping 26 matching lines @@
   <message name="IDS_LOGIN_PUBLIC_ACCOUNT_SIGNOUT_REMINDER" desc="Text shown in the public account user pod, reminding the user to log out.">
     Please remember to sign out when you're done.
   </message>
   <message name="IDS_LOGIN_PUBLIC_ACCOUNT_ENTER" desc="Label text for the sign-in button in the public account user pod.">
     Enter
   </message>
   <message name="IDS_LOGIN_PUBLIC_ACCOUNT_ENTER_ACCESSIBLE_NAME" desc="Text to be spoken when focus is set to the sign-in button in the public account user pod.">
     Enter public session
   </message>
 </grit-part>