Adds a new checkbox for backup and restore in opt-in flow.

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="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 6669 matching lines @@
   <message name="IDS_ARC_OPT_IN_DIALOG_PROGRESS_ANDROID" desc="Name of Android loading progress of the opt-in dialog for Android apps.">
     This may take up to a minute or so...
   </message>
   <message name="IDS_ARC_OPT_IN_DIALOG_AUTHORIZATION_FAILED" desc="Error message shown when an auth code is not returned by server.">
     Authorization failed
   </message>
   <message name="IDS_ARC_OPT_IN_DIALOG_TERMS_OF_SERVICE" desc="Terms of service caption in the opt-in dialog for Android apps.">
     Terms of Service
   </message>
   <message name="IDS_ARC_OPT_IN_DIALOG_METRICS_MANAGED_ENABLED" desc="Message in the opt-in dialog for Android apps in case metrics are managed on the device and on.">
-    This device will automatically send diagnostic and usage data to Google. This <ph name="BEGIN_LINK1">&lt;a href="#" id="settings-link"&gt;</ph>setting<ph name="END_LINK1">&lt;/a&gt;<ex>&lt;/a&gt;</ex></ph> is enforced by your administrator. <ph name="BEGIN_LINK2">&lt;a href="#" id="learn-more-link"&gt;</ph>Learn More<ph name="END_LINK2">&lt;/a&gt;<ex>&lt;/a&gt;</ex></ph>
+    This device will automatically send diagnostic and usage data to Google. This <ph name="BEGIN_LINK1">&lt;a href="#" id="settings-link"&gt;</ph>setting<ph name="END_LINK1">&lt;/a&gt;<ex>&lt;/a&gt;</ex></ph> is enforced by your administrator. <ph name="BEGIN_LINK2">&lt;a href="#" id="learn-more-link-metrics"&gt;</ph>Learn More<ph name="END_LINK2">&lt;/a&gt;<ex>&lt;/a&gt;</ex></ph>
   </message>
   <message name="IDS_ARC_OPT_IN_DIALOG_METRICS_MANAGED_DISABLED" desc="Message in the opt-in dialog for Android apps in case metrics are enabled on the device and off.">
-    Your administrator may choose to send diagnostic and usage data for this device to Google. You may view this <ph name="BEGIN_LINK1">&lt;a href="#" id="settings-link"&gt;</ph>setting<ph name="END_LINK1">&lt;/a&gt;<ex>&lt;/a&gt;</ex></ph> here. <ph name="BEGIN_LINK2">&lt;a href="#" id="learn-more-link"&gt;</ph>Learn More<ph name="END_LINK2">&lt;/a&gt;<ex>&lt;/a&gt;</ex></ph>
+    Your administrator may choose to send diagnostic and usage data for this device to Google. You may view this <ph name="BEGIN_LINK1">&lt;a href="#" id="settings-link"&gt;</ph>setting<ph name="END_LINK1">&lt;/a&gt;<ex>&lt;/a&gt;</ex></ph> here. <ph name="BEGIN_LINK2">&lt;a href="#" id="learn-more-link-metrics"&gt;</ph>Learn More<ph name="END_LINK2">&lt;/a&gt;<ex>&lt;/a&gt;</ex></ph>
   </message>
   <message name="IDS_ARC_OPT_IN_DIALOG_METRICS_ENABLED" desc="Message in the opt-in dialog for Android apps in case metrics are already enabled on the device. User has no way to deactivate them using opt-in dialog.">
-    This device will automatically send diagnostic and usage data to Google. You can change this at any time in your device <ph name="BEGIN_LINK1">&lt;a href="#" id="settings-link"&gt;</ph>settings<ph name="END_LINK1">&lt;/a&gt;<ex>&lt;/a&gt;</ex></ph>. <ph name="BEGIN_LINK2">&lt;a href="#" id="learn-more-link"&gt;</ph>Learn More<ph name="END_LINK2">&lt;/a&gt;<ex>&lt;/a&gt;</ex></ph>
+    This device will automatically send diagnostic and usage data to Google. You can change this at any time in your device <ph name="BEGIN_LINK1">&lt;a href="#" id="settings-link"&gt;</ph>settings<ph name="END_LINK1">&lt;/a&gt;<ex>&lt;/a&gt;</ex></ph>. <ph name="BEGIN_LINK2">&lt;a href="#" id="learn-more-link-metrics"&gt;</ph>Learn More<ph name="END_LINK2">&lt;/a&gt;<ex>&lt;/a&gt;</ex></ph>
   </message>
   <message name="IDS_ARC_OPT_IN_DIALOG_METRICS_DISABLED" desc="Message in the opt-in dialog for Android apps in case metrics are disabled on the device. User has an option to active them using opt-in dialog">
-    Automatically send diagnostic and usage data to Google. You can change this at any time in your device <ph name="BEGIN_LINK1">&lt;a href="#" id="settings-link"&gt;</ph>settings<ph name="END_LINK1">&lt;/a&gt;<ex>&lt;/a&gt;</ex></ph>. <ph name="BEGIN_LINK2">&lt;a href="#" id="learn-more-link"&gt;</ph>Learn More<ph name="END_LINK2">&lt;/a&gt;<ex>&lt;/a&gt;</ex></ph>
+    Automatically send diagnostic and usage data to Google. You can change this at any time in your device <ph name="BEGIN_LINK1">&lt;a href="#" id="settings-link"&gt;</ph>settings<ph name="END_LINK1">&lt;/a&gt;<ex>&lt;/a&gt;</ex></ph>. <ph name="BEGIN_LINK2">&lt;a href="#" id="learn-more-link-metrics"&gt;</ph>Learn More<ph name="END_LINK2">&lt;/a&gt;<ex>&lt;/a&gt;</ex></ph>
+  </message>
+  <message name="IDS_ARC_OPT_IN_DIALOG_BACKUP_RESTORE" desc="Message in the opt-in dialog for Android apps in case backup and restore is disabled on the device. User has an option to activate them using opt-in dialog">
+    Automatically back up and restore Play app data to Google Drive. You can change this in Android Settings at any time. <ph name="BEGIN_LINK1">&lt;a href="#" id="learn-more-link-backup-restore"&gt;</ph>Learn More<ph name="END_LINK1">&lt;/a&gt;<ex>&lt;/a&gt;</ex></ph>
   </message>
   <message name="IDS_ARC_OPT_OUT_TAB_TITLE" desc="Tab title when viewing opt-out setting dialog for android apps.">
     Settings - Remove Android apps
   </message>
   <message name="IDS_ARC_OPT_OUT_DIALOG_HEADER" desc="Title of the opt-out dialog for android apps.">
     Remove Android apps?
   </message>
   <message name="IDS_ARC_OPT_OUT_DIALOG_DESCRIPTION" desc="Describes what will happen if the user opts out of android apps.  Note that newlines are preserved when this is rendered in the UI.">
     Apps you’ve downloaded from Google Play will be deleted from this Chromebook.
 
@@ skipping 46 matching lines @@
   <message name="IDS_CRITICALLY_LOW_DISK_NOTIFICATION_TITLE" desc="Title of the notification warning users that they are critically low on disk space.">
     Device disk space critically low
   </message>
   <message name="IDS_CRITICALLY_LOW_DISK_NOTIFICATION_MESSAGE" desc="Notification text warning users that they are critically low on disk space.">
     Free up disk space or device will become unresponsive.
   </message>
   <message name="IDS_LOW_DISK_NOTIFICATION_BUTTON" desc="Button on the low disk notification to open storage management.">
     Manage storage
   </message>
 </grit-part>