Revert "release-combined.tested: Temporarily remove the Chromium test"
Revert "release-combined.tested: Temporarily remove the Chromium test"

This reverts commit 2dbd08dcbd5fa78d6716aa1fbdfb04be175e4162.

I've fixed the regression in 8a7a8442c17 and the rest of my
refactorings/improvements shouldn't affect the stability of the test.

NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs