Merge pull request #793 from erikvold/784224-2

Fix Bug 784224: Page-mod tests now work on Fennec r=@ochameau(cherry picked from commit 133c45791de94125e39b98aa11e3d8a9153e0153)

Conflicts:
	lib/sdk/tabs/utils.js
	test/test-page-mod.js
Merge pull request #772 from ochameau/page-mod-pb

Bug 834960: Ignore private document unless addon explicitely support private browsing r=@erikvold(cherry picked from commit 424f66c3663d8d507407952ac8586ab4bc809396)
Merge pull request #857 from ZER0/private-selection2/834958

Fix Bug 834958 - pwpb update selection module to ignore private windows r=@erikvold(cherry picked from commit a0f371fdf21a691186ad7da540f3bdb87079ee3c)
Merge pull request #853 from erikvold/845387

Bug 845387: private-browsing isPrivate should take a content script instance(cherry picked from commit 86d1660710cd4436c8e076a4142ddfc923af4140)
Merge pull request #858 from erikvold/851161

Fix Bug 851161 preventing panels from being used with per-window private browsing r=@Gozala(cherry picked from commit 707eca737187f2e825be9aa6a539c9e7934ef077)
Merge pull request #865 from erikvold/stabilization

Bug 841823: Stabilization branch updates for minimal support of per window private browsing. r=me