code: function isLabeledBy(node, labelName) {
          for (var owner = node.parent; owner.kind === 214 /* LabeledStatement */; owner = owner.parent) {
              if (owner.label.text === labelName) {
                  return true;
              }
          }
          return false;
      }
docs: Whether or not a 'node' is preceded by a label of the given string.
  Note: 'node' cannot be a SourceFile.