src/vs/workbench/contrib/files/common/explorerModel.ts/ExplorerModel/constructor
class ExplorerModel:	constructor(
		private readonly contextService: IWorkspaceContextService,
		private readonly uriIdentityService: IUriIdentityService,
		fileService: IFileService
	) {
		const setRoots = () => this._roots = this.contextService.getWorkspace().folders
			.map(folder => new ExplorerItem(folder.uri, fileService, undefined, true, false, false, folder.name));
		setRoots();

		this._listener = this.contextService.onDidChangeWorkspaceFolders(() => {
			setRoots();
			this._onDidChangeRoots.fire();
		});
	}