MediaScanner: Do not update the file path when updating records already in the database

The path should never change (media scanner treats renames as a delete and an insert)
and we want to preserve the mixed case paths in the database to avoid exposing the
lowercase squashing to MTP.

Change-Id: I79ef37e143c607242d438a4a0643d40191965b6a
Signed-off-by: Mike Lockwood <lockwood@android.com>

media/java/android/media/MediaScanner.java

@@ -784,6 +784,9 @@ public class MediaScanner
             } else {
                 // updated file
                 result = ContentUris.withAppendedId(tableUri, rowId);
+                // path should never change, and we want to avoid replacing mixed cased paths
+                // with squashed lower case paths
+                values.remove(MediaStore.MediaColumns.DATA);
                 mMediaProvider.update(result, values, null, null);
             }
             if (mProcessGenres && mGenre != null) {