Bug 1000323 - Reauthenticate the user when disabling Find My Device.
Bug 1039931 - [gaia][system] Replace __proto__ with Object.create

* Remove usages of __proto__ in the system app.
Merge pull request #21129 from guilherme-pg/bug1000323-force-reauth-when-disabling

Bug 1000323 - Reauthenticate the user when disabling Find My Device. r=gerard-majax
Bug 1038326 - Fix layout issues with searchWindow and children. r=alive
Merge pull request #21853 from begeeben/1039931_replace__proto__

Bug 1039931 - [gaia][system] Replace __proto__ with Object.create, r=alive
Bug 994571 - [System2] Remove the pattern to return self in start()

* Remove 'var module = new Module().start()' pattern.
* Remove 'return this;' expression in start() function definitions.