Unhide KeyguardManager locked and secure state getters

Unhide the following methods:
  android.app.KeyguardManager.isKeyguardLocked()
  android.app.KeyguardManager.isKeyguardSecure()

Fix some javadoc typos

Change-Id: Iedcd9f6a5261b7a3b47431edff013f629e1dc45d
3 files changed