It's about time for us to add a build-time option for per-window private browsing, so that we can focus on getting the latest remaining pieces landed on mozilla-central without having to switch to a feature which is half-done on Nightly. We'll develop the parts which can only be turned on whole-sale behind this build-time flag, and once we're ready, we'll turn it on by default, and remove the old code which relies on global private browsing. The configure option can be called --enable-per-window-private-browsing, and the macro defined by it can be called MOZ_PER_WINDOW_PRIVATE_BROWSING. Or feel free to choose any other name, the naming is the least important part. :-)
No need for a configure option, just AC_SUBST(MOZ_PER_WINDOW_PRIVATE_BROWSING), and export MOZ_PER_WINDOW_PRIVATE_BROWSING=1 in your mozconfig instead of ac_add_options --enable-per-window-private-browsing.
(In reply to Mike Hommey [:glandium] from comment #1) > No need for a configure option, just > AC_SUBST(MOZ_PER_WINDOW_PRIVATE_BROWSING), and export > MOZ_PER_WINDOW_PRIVATE_BROWSING=1 in your mozconfig instead of > ac_add_options --enable-per-window-private-browsing. That's an excellent suggestion, thanks!
Created attachment 639756 [details] [diff] [review] Patch (v1) Stealing this, as it seems like we really need it soon.