Issue #3259751 by rodrigoaguilera, smustgrave, nod_: Add ability to pass cli arguments to chromedriver

Issue #2869825 by justafish, dawehner, alexpott, martin107, jibran, Lendude, Mixologic, michielnugter, droplet, drpal, lauriii, effulgentsia, mglaman: Leverage JS for JS testing (using nightwatch)