chromium does not build on master / dunfell - Enable Python 2 Support

Close for JJ RC1

Chromium is now compiling fine with the inclusion of `meta-python2`. The building of the entire HTML5 image however, is still not working due to some needed updates on the webapps due to .

As commented on the call today, it was decided to make available temporary that layer, in order to have time to update/backport into our Chromium the changes to be able to build without Python2 anymore.

There was mention on last week's YP technical call that upstream Chromium was working on Python 3 support, but I've not gone and looked to see what state that's in.  One option would be to perhaps try adding meta-python2 when enabling agl-profile-graphical-html5 as a stopgap measure for now.

So as it seems that Dunfell is removing Python2 support, I'm checking for a way to avoid the issue on Chromium https://lwn.net/Articles/818376/