Fix quick settings user switcher avatar shape issue.

In older OS versions user photos weren't cropped to round shape, so a
legacy user avatar had a rectangular shape in the QS user switcher.
I've added on the fly shaping (similar to how it works in the Settings
app) to QS user avatars.

Test: manual test
Bug: 159473281
Change-Id: Iea48f01aa2f94a2ca5adb3e46eea7c3947092447
3 files changed