Simple helper class used to observe a simple closure and report its behavior over time.
BoolMonitor is used by
OVRControllerTest to conveniently serialize controller behavior into a human-readable format. For example, a test of OVRInput.Button.One will observe OVRInput.Get(OVRInput.Button, OVRInput.Controller) with that input, displaying the monitor's name and current state in the format, "One: *True*," etc.