Tracks without Album-artist and without label are hidden when First Level Label and Second Level Album-artist are selected.

Reproducible: Always

Steps to Reproduce:
1. Have a collection with 12 Tracks, 
    10 without Album artist field set and without label (a)
      1 without Album artist field set and but labeled (b)
      1 with  Album artist field set and without label (c)
2. Set "First Level" to Label (The menu entry under the tool/gear above the collection)
3. Set "Second Level" to Album artist
Actual Results:  
a) The collection heading says the collection has 12 Tracks.
b) The 10 tracks (a) are hidden because there is no "Various artists" entry under "No label".
c) Track (b) is shown in "Various Artists" under the label
d) Track (c) is show under the "Album Artist" under "No Label"

Expected Results:  
a), c), d) are ok. 
b) The tracks should be  "No Label" - "Various Artists"