Create a Keyguard Status Checker

- keyguard system status checker to ensure state of
  keyguard.
- Allow keyguard disable to try new 'wm dismiss-keyguard'
  before falling back to old way.

Test: unit tests, func tests
Bug: 29870342
Change-Id: Ia08006ed2793f257fe5ce3b07e99cd2f3eaed156
6 files changed