src/vs/workbench/contrib/tasks/common/problemCollectors.ts/AbstractProblemCollector/getResourceSetToClean
class AbstractProblemCollector:	private getResourceSetToClean(owner: string): Map<string, URI> {
		let result = this.resourcesToClean.get(owner);
		if (!result) {
			result = new Map<string, URI>();
			this.resourcesToClean.set(owner, result);
		}
		return result;
	}