Fixes #40076: "Explore privately" not visible entirely in French

Bug 40068: Tor Service closes when changing theme

Part of #40078 fix.

Fixes #40086: Disabling/Enabling addon still shows option to
disallow in private mode.

Bug 40082: Use Security Level preference at startup

Bug 40053: Provide feedback in onboarding Security Level card

Alex Catarineu authored Oct 06, 2020 and Matthew Finkel committed Oct 10, 2020

Also 40070: Consider storing the list of recommended addons

This implements our own AddonsProvider, which loads the list of
available addons from assets instead of fetching it from an
endpoint. In this list, we replace https-everywhere by
our https-everywhere-eff, so that the EFF one is shown as installed
in the addons list and the AMO one is not displayed.

Also, we hide the uninstall button for builtin addons.

Georg Koppen authored Oct 01, 2020 and Matthew Finkel committed Oct 07, 2020

We make sure our MOZ_BUILD_DATE gets used as a source for showing date
related information on the Fenix about page.

Georg Koppen authored Sep 25, 2020 and Matthew Finkel committed Oct 07, 2020

At the same time we adapt MOZ_BUILD_DATE to our needs where it is
actually used and not in tor-browser-build. This gives us more
flexibility. See: tor-browser-build#40084.

Alex Catarineu authored Sep 22, 2020 and Matthew Finkel committed Oct 07, 2020

With the corresponding android-components patch, this allows all `startActivity`
that may open external apps to be replaced by `TorUtils.startActivityPrompt`.