Revert unwanted change

Author: johannalee

README.md

@@ -93,7 +93,7 @@ function* treeWalker(refresh) {
 
     // Basing on the node openness state we are deciding if we need to render
     // the child nodes (if they exist).
-    if (children.length > 0 && isOpened) {
+    if (children.length !== 0 && isOpened) {
       // Since it is a stack structure, we need to put nodes we want to render
       // first to the end of the stack.
       for (let i = children.length - 1; i >= 0; i--) {