"year" and "track number" are set to 1700 and 1 instead of deletion

Submitted by gm...@..il.com

Assigned to Jannis Pohlmann

Link to original bug (#6341)

Description

I tried to clear year and track number tags. I deleted them and pressed "Save" button, and they were set to 1700 (year) and 1 (track number). IMHO the right action is to remove tags from file.