[Multi-user] Show Backup only if Backup is activated

This almost reverts the change to SettingsActivity#doUpdateTilesList in ag/6140694
except that instead of setting enabled to true, we set it to whether
backup is activated for this user.

Bug: 124114084

Test: 1a) Set up secondary user
1b) See that there is no Backup option in Settings Homepage - System
1c) adb shell bmgr --user 10 activate true
1d) Backup option is now present
1e) adb shell bmgr --user 10 activate false
1f) Backup option isnt there again

Change-Id: I3f17aabee92bedc91386444c2f0aede696d0fd13

src/com/android/settings/SettingsActivity.java

@@ -50,6 +50,8 @@ import androidx.preference.PreferenceManager;
 import com.android.internal.util.ArrayUtils;
 import com.android.settings.Settings.WifiSettingsActivity;
 import com.android.settings.applications.manageapplications.ManageApplications;
+import com.android.settings.backup.BackupSettingsHelper;
+import com.android.settings.backup.UserBackupSettingsActivity;
 import com.android.settings.core.OnActivityResultListener;
 import com.android.settings.core.SettingsBaseActivity;
 import com.android.settings.core.SubSettingLauncher;
@@ -630,6 +632,12 @@ public class SettingsActivity extends SettingsBaseActivity
                 showDev, isAdmin)
                 || somethingChanged;
 
+        // Enable/disable backup settings depending on whether backup is activated for the user.
+        boolean isBackupActive = new BackupSettingsHelper(this).isBackupServiceActive();
+        somethingChanged = setTileEnabled(changedList, new ComponentName(packageName,
+                UserBackupSettingsActivity.class.getName()), isBackupActive, isAdmin)
+                || somethingChanged;
+
         somethingChanged = setTileEnabled(changedList, new ComponentName(packageName,
                         Settings.WifiDisplaySettingsActivity.class.getName()),
                 WifiDisplaySettings.isAvailable(this), isAdmin)