Use FalsingManager for QS user switcher

Bug: 192013256
Test: atest SystemUITests:com.android.systemui.qs.QSFragmentTest
Test: atest SystemUITests:com.android.systemui.qs.QSDetailTest
Change-Id: I9587aa375e8f9e5ef7d696fcb3f0904cf546c0cc
Merged-In: I9587aa375e8f9e5ef7d696fcb3f0904cf546c0cc
6 files changed