Internal trackers APIs

[eupp]

This PR implements a refactoring to introduce separate internal event trackers API:

• MonitorTracker tracks monitor events (lock, unlock, wait, notify)
• ParkingTracker tracks parking events (park, unpark)
• ObjectTracker tracks new objects creation and changes in object graph topology.

Different strategies can implement these tracker interfaces for their needs.

We need this refactoring for two features:

• new model checking strategy need to implement its own logic for tracking aforementioned events;
• to support blocking operations, stress strategy also need to track parking events.

[eupp]

@avpotapov00 could you please have a look at this PR and check if it aligns with your vision for the parking tracker for stress strategy.

[eupp]

@ndkoval ready for review.
We also discussed it with @avpotapov00 , he is also good with these changes.

[ndkoval]

@eupp, great, I will take a look at the PR. Meanwhile, could you please investigate why the build on Windows has failed?

[eupp]

Meanwhile, could you please investigate why the build on Windows has failed?

Looks like unrelated flakiness problem. I've re-run the build and it is green now.

[ndkoval]

Should it return false if the execution has finished?

[eupp]

By "execution has finished" do you mean "all other threads finished"?

At least in current implementation, ParkingTracker does not have access to threads "finish status" info. Parking tracker only stores parked boolean flags for each thread.

[eupp]

So can I merge this PR? @ndkoval

[ndkoval]

Hi @eupp, I've approved the PR. Thanks for extracting the logic and improving the code structure!

I've left a minor comment -- please address it and merge the PR.