Create a state for the camera and microhpone toggles

This change adds the simple getters and setters for the state of the
toggles. The persisted xml format is backwards compatible so no
migration is needed.

Test: None for new state
      Verify old sensor mute works the same
Bug: 162549680

Change-Id: I6a1ef9c703cc5d175c1a5f788a3559eabf0054ad