SysUI: Log lockscreen state to eventlog

Logs the following keyguard and status bar states to
eventlog:
  * statusBarState
  * keyguardShowing
  * keyguardOccluded
  * bouncerShowing
  * secure
  * currentlyInsecure

Bug: 18767135
Change-Id: If27a9340dd1b5ec609f9940d9e0f32bd7aed1ed2
7 files changed