Merge pull request #4467 from paulkaplan/fix-backpack-code-updating

Call updateToolbox after adding new blocks from the backpack.

src/containers/blocks.jsx

@@ -455,6 +455,7 @@ class Blocks extends React.Component {
             .then(blocks => this.props.vm.shareBlocksToTarget(blocks, this.props.vm.editingTarget.id))
             .then(() => {
                 this.props.vm.refreshWorkspace();
+                this.updateToolbox(); // To show new variables/custom blocks
             });
     }
     render () {