Before this patch, we only considered the primary screen when deciding
whether or not WebRender should be enabled. This is problematic for
Intel users where we don't want to turn on WebRender for large screens;
several small screens are just as bad as one large screen. Now we sum
the pixel count for all the screens when making this decision.
Differential Revision: https://phabricator.services.mozilla.com/D46066
--HG--
extra : moz-landing-system : lando
