Show also tracks without album in artist view

[pv]

Expected behavior

The artist view in http://127.0.0.1:6680/iris/#/artist/local%3Aartist%3Amd5%3A... should show all tracks that the artist has in the local database, including those tracks that are not associated with an album. I would expect the album-less tracks appear on the page e.g. grouped under a [no album] album.

Actual behavior

Tracks that are not associated with an album (i.e. have missing/empty album field in the metadata) are not visible in the artist view /iris/#/artist/local%3Aartist%3Amd5%3A...
(except possibly in the "top tracks" list that is limited to 10 items.)

They are visible in the "Local media" browse interface under
/iris/#/library/browse/local%3Aartist%3Amd5%3A... However, the artist links provided by the search interface take you to the /iris/#/artist/local page and not to /iris/#/library/browse/local, so it would be better to have the two be consistent.

Steps to replicate

1. Have tracks with artist but without album metadata in the local database.
2. Search for the artist, and click the local artist link in search (or browse via "Artists")
3. The artist page shows an empty album list, with only "Top tracks" shown (but that is limited to 10 items), so there's no way to see all of the tracks.

Example:

$ vorbiscomment -l tmp.ogg 
TITLE=Some Test Track title
ARTIST=Some Test Artist
REPLAYGAIN_TRACK_PEAK=1.23274279
REPLAYGAIN_TRACK_GAIN=-7.72 dB
REPLAYGAIN_ALBUM_PEAK=1.23274279
REPLAYGAIN_ALBUM_GAIN=-7.72 dB

Search results for "Some Test artist".

Screen after clicking the artist in search results. The album list is empty, and the tracks appear only in the "Top tracks list" --- however, the "Top tracks" show only maximum of 10 items, so there's no way to see all the tracks the artist has available in the local database:

Tested environment(s)

Operating systems affected

• Windows:
• Mac:
• Linux:
• iOS:
• Andriod:
• Other:

Browsers affected

• Chrome:
• Firefox:
• Internet Explorer:
• Opera:
• Other:

Screen sizes affected

• Huge (ie desktop)
• Large (ie laptop)
• Medium (ie slim laptop/tablet)
• Small (phone)

Additional details, debug data, logs, etc

Probably none required.
Mopidy==2.2.1
Mopidy-Iris==3.31.3

Before you submit

• Yes, I have tested this issue thoroughly
• Yes, I have attached screenshots and/or screencast of the issue in action
• Yes, I have included any relevant debug data and error logs