Do not render children of non-expanded nodes

Addresses performance of #14.

Author: jakezatecky

src/js/Tree.js

@@ -155,7 +155,7 @@ class Tree extends React.Component {
 	}
 
 	renderChildNodes(node) {
-		if (this.hasChildren(node)) {
+		if (this.hasChildren(node) && node.expanded) {
 			return this.renderTreeNodes(node.children);
 		}
 

src/js/TreeNode.js

@@ -42,7 +42,7 @@ class TreeNode extends React.Component {
 	}
 
 	renderCollapseIcon() {
-		if (this.props.children === null) {
+		if (this.props.rawChildren === undefined) {
 			return <i className="fa" />;
 		}
 
@@ -66,7 +66,7 @@ class TreeNode extends React.Component {
 	}
 
 	renderNodeIcon() {
-		if (this.props.children !== null) {
+		if (this.props.rawChildren !== undefined) {
 			if (!this.props.expanded) {
 				return <i className="fa fa-folder-o" />;
 			}