visitChildren method
Visit this node's children. This is the method that actually understands
the structure of the node. It should invoke Visitor.visit etc on all the
node's children.
This method must be implemented if the node has children. The
implementation should call super.visitChildren(visitor);.
Implementation
@override
void visitChildren(Visitor visitor) {
super.visitChildren(visitor);
visitor.visit(libraryImport);
}