@chinmaygarde this had to be reverted due to framework roll failure. I triggered a manual roll with this one change: flutter/flutter#81404 and it succeeded. Looks like the failures were flakes.

Sorry for disturb. Is there any public shared docs indicating the improvement? go/flutter-engine-task-prioritization seems invalid.

Does Flutter not need to adhere to the semantics of microtask?

This PR appears to have disrupted the semantics of microtasks (https://dart.cn/articles/archive/event-loop):

The microtask queue is necessary because event-handling code sometimes needs to complete a task later, but before returning control to the event loop. For example, when an observable object changes, it groups several mutation changes together and reports them asychronously. The microtask queue allows the observable object to report these mutation changes before the DOM can show the inconsistent state.

See https://jakearchibald.com/2015/tasks-microtasks-queues-and-schedules/ for more details.