Fix default ring/alarm/notification insertion

Before directly inserting an item that is the default ringtone, alarm or
notification, flush the MediaInserter, since a parent of the inserted item
might not have been flushed yet.

b/7650557

Change-Id: Icdd25bd9cac8b43a75e63318b936246562744c59

media/java/android/media/MediaScanner.java

@@ -958,6 +958,7 @@ public class MediaScanner
                 // If the rowId of the inserted file is needed, it gets inserted immediately,
                 // bypassing the bulk inserter.
                 if (inserter == null || needToSetSettings) {
+                    inserter.flushAll();
                     result = mMediaProvider.insert(tableUri, values);
                 } else if (entry.mFormat == MtpConstants.FORMAT_ASSOCIATION) {
                     inserter.insertwithPriority(tableUri, values);