They landed in: http://hg.mozilla.org/mozilla-central/diff/254300336b6b/browser/base/content/tabcandy/app/groups.js ... back in July, and I have no idea what they're for. Ehsan has pointed out they're entirely write-only, so we should be able to pull them right out.
Of course this has to be double-checked before being removed. I basically did a grep in browser/base/content/tabview and we only write to it there. I didn't investigate it further.
xDensity and yDensity are indeed currently not being used. I wanted some notion like this, a while ago, in preparation for rewriting the squishing code. The idea is that I could look at xDensity and yDensity to see whether it would be more or less "costly" to squish a group a certain way. We can kill this for now, though, and if the rewrite of squish needs to use this, we can reintroduce it then.
Created attachment 488784 [details] [diff] [review] Patch
Comment on attachment 488784 [details] [diff] [review] Patch Looking good.
Does it need a try run?
Sent to try: 1524975ec79c Can we get approval for this?
Created attachment 492219 [details] [diff] [review] Cleaned up patch (exactly what was pushed to try just now)
(In reply to comment #7) > Created attachment 492219 [details] [diff] [review] > Cleaned up patch (exactly what was pushed to try just now) Sorry, just to clarify: this is just to counter the rot.
Created attachment 493332 [details] [diff] [review] Patch for checkin First try run had a lot of intermittent orange. Tried another run today which came out clean. Ready to checkin.
verified per try runs