Revert "Issue #2822382 by voleger, pfrenssen, erozqba, RytoEX, borisson_, sidharthap, Jo Fitzgerald, shashikant_chauhan: Make every  property protected on classes extending BrowserTestBase and KernelTestBase"

This reverts commit 29d0958a.

Issue #2822382 by voleger, pfrenssen, erozqba, RytoEX, borisson_, sidharthap, Jo Fitzgerald, shashikant_chauhan: Make every  property protected on classes extending BrowserTestBase and KernelTestBase

(cherry picked from commit 69501f30)

Issue #2942900 by Mixologic, vaplas, jibran, dawehner, Lendude, martin107, alexpott, tedbow, tacituseu, tstoeckler, heddn: Convert JavascriptTestBase Tests to use DrupalSelenium2Driver

Revert "Issue #2942900 by Mixologic, vaplas, jibran, Lendude, martin107, alexpott, dawehner, tedbow, tacituseu, tstoeckler, heddn: Convert JavascriptTestBase Tests to use DrupalSelenium2Driver"

This reverts commit f55d9746.

Issue #2942900 by Mixologic, vaplas, jibran, Lendude, martin107, alexpott, dawehner, tedbow, tacituseu, tstoeckler, heddn: Convert JavascriptTestBase Tests to use DrupalSelenium2Driver

Issue #2764931 by tedbow, tim.plunkett, nod_, drpal, droplet, dawehner, Wim Leers, phenaproxima: Contextual links don't work with 'use-ajax' links

Issue #2650910 by drpal, Anishnirmal, markdorison, Tom Robert, psend, yannickoo, rachel_norfolk, Wim Leers, droplet: Contextual links button is always rendered even when no links are available (with warm client-side cache)