src/vs/editor/contrib/linesOperations/browser/linesOperations.ts/DeleteDuplicateLinesAction/constructor
class DeleteDuplicateLinesAction:	constructor() {
		super({
			id: 'editor.action.removeDuplicateLines',
			label: nls.localize('lines.deleteDuplicates', "Delete Duplicate Lines"),
			alias: 'Delete Duplicate Lines',
			precondition: EditorContextKeys.writable
		});
	}