2.0 tree example bug

[aviggngyv]

Well, I know this issue is repeat with #2994, I just want to report this issue, because I note today, new dist/vue.js file is releases, I updated this for my project ,then I get same error code when execute push operating:

vue.js:2137 [Vue warn]: Error during component render (found in component: )warn @ vue.js:2137get @ vue.js:626run @ vue.js:719runSchedulerQueue @ vue.js:537flushSchedulerQueue @ vue.js:506nextTickHandler @ vue.js:342
vue.js:2137 [Vue warn]: Error: Failed to execute 'insertBefore' on 'Node': The node before which the new node is to be inserted is not a child of this node.

then I found #2994 issue by search, then I found the tree example still have this bug, I hope those infomation is useful to fix it.

Thanks.

[yyx990803]

I can't reproduce this - can you list the detailed steps that lead to the mentioned error?

[aviggngyv]

Look this gif, you will got it , thanks for all your hard work ! Vuejs changed my life!

[yyx990803]

Thanks for the repro, fixed in next branch.