fix npe

src/vs/workbench/browser/labels.ts

@@ -210,15 +210,20 @@ export class FileLabel extends ResourceLabel {
 	}
 
 	public setFile(resource: uri, options?: IFileLabelOptions): void {
+		const hideLabel = options && options.hideLabel;
 		let name: string;
-		if (options && options.hideLabel) {
-			name = void 0;
-		} else if (options && options.fileKind === FileKind.ROOT_FOLDER) {
+		if (!hideLabel) {
+			if (options && options.fileKind === FileKind.ROOT_FOLDER) {
 				const workspaceFolder = this.contextService.getWorkspaceFolder(resource);
+				if (workspaceFolder) {
 					name = workspaceFolder.name;
-		} else {
+				}
+			}
+
+			if (!name) {
 				name = paths.basename(resource.fsPath);
 			}
+		}
 
 		let description: string;
 		const hidePath = (options && options.hidePath) || (resource.scheme === Schemas.untitled && !this.untitledEditorService.hasAssociatedFilePath(resource));