Improve QuickSettingActivity to show managed device info

After setup device owner, open quick setting.
There should be text above build information indicating the device is
managed.
Additionally, user switcher button on top right corner should show user
icon with badge indicating the current user is managed.

Bug: 178039342
Test: manual verification
Change-Id: I8ea98cc5fb733b654d7fcc31ca7929258f98f53d
3 files changed