Adding unfold latency tracking to DisplaySwitchLatencyTracker

Using current logic of DisplaySwitchLatencyTracker to track latency using LatencyTracker.
Logic is also adjusted to exclude invalid cases when many fold/unfold events were emitted without finish event and it was measured as one very long display switch. This is done using cool-down mechanism:
1. When new start transition event is emitted before we managed to get finish event, we enter cool-down state (isCoolingDown field)
2. Cool-down lasts 2 seconds and is restarted for every new start or end event emitted while in cool-down, see startCoolDown method.
3. After cool-down times out, we are back to normal operation

Old version of DisplaySwitchLatencyTracker is copied as NoCooldownDisplaySwitchLatencyTracker and will be used when unfold_latency_tracking_fix flag is off.

Bug: 390649568
Test: DisplaySwitchLatencyTrackerTest
Flag: com.android.systemui.unfold_latency_tracking_fix
Change-Id: I8511fcea94fd234b690e56cce144412822095db9