Updating nodes in tree with virtual scroll breaks tree - like load more nodes function

Minimal reproduction of the bug/regression with instructions:

Updating nodes and calling treeModel.update() with virtual scroll leads to a collapsing tree and finally a tree stuck in loading… This is only present in virtual scroll. Setting virtual scroll to false will fix the problem.

Stackblitz uses an example where the child nodes are loaded in steps with a load more functionality 100 nodes each time.

Link to Stackblitz reproduction

Repo steps:

• Open root node
• Click load more
• Root node will collapse
• If this is repeated multiple times tree is stuck in loading…

Expected behavior:

Tree behaves the same in virtual and non-virtual scroll.

Versions of Angular Tree Component, Angular, Node, affected browser(s) and operating system(s):

First noticed in version 8.5, still there in 10.0.0.

Other information:

[tobiasengelhardt]

Can confirm that removing the ngZone fixes the update issue and has very good performance. @Cowraider, when you have your PR ready we will merge it into the repo.

Because this issue is in a few versions we will release this fix in all the mayor versions with the @circlon namespace (11, 10 and 9).

[alechemy]

🎉 Great work @Cowraider , and my apologies for inadvertently creating this issue.