[DO NOT MERGE] Update title for null uri when setting changes am: ea14373666

am: c48918dac0

Change-Id: I268d4d01a515e1c49b83e3c321af230cb06bffc9

src/com/android/settings/notification/RingtonePreferenceControllerBase.java

@@ -55,7 +55,7 @@ public abstract class RingtonePreferenceControllerBase extends AbstractPreferenc
 
         final CharSequence summary;
         if (ringtoneUri == null) {
-            summary = null;
+            summary = mContext.getString(com.android.internal.R.string.ringtone_silent);
         } else {
             summary = Ringtone.getTitle(
                     mContext, ringtoneUri, false /* followSettingsUri */, true /* allowRemote */);