src/vs/workbench/contrib/tasks/common/problemCollectors.ts/AbstractProblemCollector/cleanMarkers
class AbstractProblemCollector:	protected cleanMarkers(owner: string): void {
		const toClean = this.resourcesToClean.get(owner);
		if (toClean) {
			this._cleanMarkers(owner, toClean);
			this.resourcesToClean.delete(owner);
		}
	}