src/vs/workbench/services/search/node/textSearchManager.ts/NativeTextSearchManager/constructor
class NativeTextSearchManager:	constructor(query: ITextQuery, provider: TextSearchProvider, _pfs: typeof pfs = pfs) {
		super(query, provider, {
			readdir: resource => _pfs.Promises.readdir(resource.fsPath),
			toCanonicalName: name => toCanonicalName(name)
		});
	}