kiosk: Network connectivity test during launch.

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>
   <message name="IDS_EMPTY_STRING" desc="Empty string, exist only to make code generic. No translation required.">
   </message>
   <!-- Idle logout dialog for retail mode -->
   <message name="IDS_IDLE_LOGOUT_TITLE" desc="Dialog title for the idle logout dialog. Used in retail mode only.">
     Are you still there?
   </message>
@@ skipping 630 matching lines @@
   </message>
   <message name="IDS_LOCAL_STATE_ERROR_TEXT_0" desc="Text for notification that Local State file is corrupted and powerwash is required.">
     Unfortunately, <ph name="SHORT_PRODUCT_NAME">$1<ex>Chrome</ex></ph> is unable to recover your settings. To fix the error, <ph name="SHORT_PRODUCT_NAME">$1<ex>Chrome</ex></ph> must reset your device with Powerwash.
   </message>
   <message name="IDS_LOCAL_STATE_ERROR_TEXT_1" desc="Text for notification that all local files will be deleted while Google account and any synced data won't be affected.">
     Resetting your device will not affect your Google accounts or any data synced to these accounts. However, all files saved locally on your device will be deleted.
   </message>
   <message name="IDS_LOCAL_STATE_ERROR_POWERWASH_BUTTON" desc="Button label to restart and powerwash the device.">
     Restart and Powerwash
   </message>
+  <message name="IDS_REBOOT_BUTTON" desc="Button label to restart the device.">
+    Reboot
+  </message>
   <message name="IDS_OFFLINE_LOGIN_HTML" desc="Text which suggests enter as an existing user when valid network isn't presented.">
     If you've already registered on this device, you can <ph name="LINK2_START">$1<ex>&gt;a&lt;</ex></ph>sign in as an existing user<ph name="LINK2_END">$2<ex>&gt;/a&lt;</ex></ph>.
   </message>
   <message name="IDS_SHUTDOWN_BUTTON" desc="Text shown on shutdown button on login/locker screen">
     Shut down
   </message>
   <message name="IDS_KIOSK_APPS_BUTTON" desc="Text shown on a button that brings up the kiosk apps menu on login screen">
     Apps
   </message>
   <message name="IDS_LOGIN_USER_ADDING_BANNER" desc="Text shown on a banner in user adding screen.">
@@ skipping 3215 matching lines @@
   <message name="IDS_FIRST_RUN_HELP_STEP_KEEP_EXPLORING_BUTTON" desc="Text on the button located in the first-run tutorial bubble pointing to help button is system tray. After click on the button tutorial finishes and help app opens.">
     Keep exploring
   </message>
   <message name="IDS_FIRST_RUN_HELP_STEP_FINISH_BUTTON" desc="Text on the button located in the first-run tutorial bubble pointing to help button is system tray. After click on the button tutorial finishes.">
     Finish
   </message>
   <message name="IDS_FIRST_RUN_NEXT_BUTTON" desc="Text on the first-run tutorial button leading to next step of tutorial.">
     Next
   </message>
 </grit-part>