Bug 999545 - Callscreen app needs write access to settings
Merge pull request #18537 from Rik/settings-readwrite-999545

Bug 999545 - Callscreen app needs write access to settings r=etienne
Revert "Bug 989923 - [Contacts][Refactor] New app to host Contacts DataStore in test apps"

This reverts commit 4552b1b8e974e3ce2d47e894100a14fecd737a00.
Bug 973454 - [settings] refactor App permissions panel with AMD pattern