src/vs/editor/common/viewModelEventDispatcher.ts/ViewModelEventDispatcher/beginEmitViewEvents
class ViewModelEventDispatcher:	public beginEmitViewEvents(): ViewModelEventsCollector {
		this._collectorCnt++;
		if (this._collectorCnt === 1) {
			this._collector = new ViewModelEventsCollector();
		}
		return this._collector!;
	}