Australis schedule update #2

[Justin Dolske]

You may find yourself behind the wheel of a large automobile.
You may find yourself in Firefox 25.
You may ask yourself, well, where is Australis?

So, allow me to provide a schedule update...

LANDING
-------

We're still planning on landing as soon as possible in Firefox 25.

We currently have three landing blockers... 2 performance regressions 
(880611, 880620) and 1 SDK test fix (885015). The test fix will be 
landing shortly, while the 2 perf bugs are still being actively 
investigated.

An accurate ETA isn't possible until we understand the regressions 
better, and that's currently the top priority.

POST-LANDING
------------

We're planning to land in 25, but also to back-out immediately after the 
uplift to Aurora (Aug 5th). Australis will stay on mozilla-central 
(only) until Firefox 26 uplifts to Aurora (Sep 16th), with intent to 
ride the 26 train thru to release. In other words, Australis will be in 
Firefox 25 Nightly builds soon, but will not go to Firefox 25 Aurora (or 
Beta, or Release). That gives ~10 weeks of m-c bake time before 26 
uplift, instead of the ~4 we have for 25.

Why are we doing this? Three reasons.

1) We have too many open bugs to realistically ship in 25. If you 
compare the numbers from last weeks "Australis Triage" email with our 
fix rate over the last month, we can definitely make a big dent in the 
bug count... Say, most of the P1 and P2 bugs, and some P3/P4/P5. But 
that would leave us needing to do more work in Aurora than is really 
acceptable, and shipping something that's not as polished as we want. 
And we'd have zero margin for dealing with new issues.

2) We want to better understand the "unknown unknowns" that will 
inevitably be found after landing. Australis touches a number of things 
related to primary UI and add-ons, and so the sooner we get onto 
mozilla-central the sooner we can see what surprises come up. (I don't 
think there's any unusual or major risk here, it's just info we need to 
know before we can ride a train with confidence.)

3) There will be some add-on compatibility issues, due to the new 
customization UI and removal of the addon-bar. Getting Australis into 
mozilla-central will spur on add-on developers to make fixes in a way 
that lingering on a project branch won't. Doing it across 25 and 26 will 
also give us extra time to do developer outreach.

Finally, it's also worth noting that Australis has really come together 
over the last 6 weeks, and it sure feels at (or even above?) the general 
quality level people can expect of a Nightly. (Try the current UX build 
for yourself, if you haven't: http://people.mozilla.org/~jwein/ux-nightly/)

Justin