For implementations of DevicePolicyKeyguardService to provide a SurfacePackage via SurfaceControlViewHost, they must be running on the UI thread. Additionally, fix dismissal logic to bypass re-checking the secondary lockscreen, and add defensive null checks. Bug: 136085151 Bug: 151365616 Test: atest AdminSecondaryLockScreenControllerTest Test: atest KeyguardUpdateMonitorTest Change-Id: Ibcd7090f50831cddbf952914adf020015750afd8