To run Selenium browser tests (bug 53697) in the PhantomJS headless browser, we need PhantomJS to come with a WebDriver.
We currently have PhantomJS 1.4 which does not have such support.
Apparently, support for the DebDriver has been added in PhantomJS v1.8:
The binding in Selenium are provided as of v2.27 (qa/browsertests ship v2.35) so at least that part is covered.
We thus need to backport PhantomJS from Ubuntu Saucy (it has v1.9.0). That will most probably have impact on the existing QUnit jobs.