code: private boolean isTypeAnnotationAllowedForName(Node n) {
      checkState(n.isName(), n);
      // Only allow type annotations on nodes used as an lvalue.
      if (!NodeUtil.isLValue(n)) {
        return false;
      }
      // Don't allow JSDoc on a name in an assignment. Simple names should only have JSDoc on them
      // when originally declared.
      Node rootTarget = NodeUtil.getRootTarget(n);
      return !NodeUtil.isLhsOfAssign(rootTarget);
    }
docs: Is it valid to have a type annotation on the given NAME node?