Add summary to "Sound" preference (1 of 2)

res/xml/preferences.xml

@@ -52,6 +52,7 @@
                             android:dependency="pref_key_enable_notifications"
                             android:key="pref_key_ringtone"
                             android:title="@string/preferences__sound"
+                            android:summary="@string/preferences__change_notification_sound"
                             android:ringtoneType="notification"
                             android:defaultValue="content://settings/system/notification_sound" />