Just tested with chromium-browser 68.0.3440.75-0ubuntu0.16.04.1 in a xenial amd64 VM, with google-chrome stable installed (68.0.3440.84-1), and widevine works.
Just tested with chromium-browser 68.0.3440. 75-0ubuntu0. 16.04.1 in a xenial amd64 VM, with google-chrome stable installed (68.0.3440.84-1), and widevine works.