[fix bug 918487] Languages results repeated for lang search on firefox all
Improve /firefox/os/ animation performance. Bug 911674.

- Update intro bgs, phone screen, adaptive bgs, adaptive
  feature points, & adaptive sprites.

- Performance in A-grade browsers seems far better (based
  on Fx repaints and Chrome frames).

- IE 9 and below get a slightly degraded experience. Can
  be improved if necessary.

- Fix IE8 bug where birthday bg would never show up in
  top fading section.
Merge pull request #1262 from jpetto/bug-911674-optimize-fx-os-adaptive-search

Improve /firefox/os/ animation performance. Bug 911674.
Bug 914694 - followup to fix bugs on production
Merge pull request #1265 from silverorange/914694-followup

bug 914694. followup to fix bugs on production
If download is not possible, don't show scene2 on /new.

See bugs 891562 and 919788.

This also prevents scene2 from appearing if you manually update the location hash. Both of these scenarios could cause bogus download stats when the page is loaded in firefox-latest or fxos or an unsupported platform.
Merge pull request #1261 from alexgibson/bug-918487-languages-results-repeated-for-lang-search-firefox-all

[fix bug 918487] Languages results repeated for lang search on firefox a...
Merge pull request #1267 from gauthierm/fix-bad-download-events

If using firefox-latest or an unsupported platform, don't show scene2 on page load.