Garbage collection deletes TabView's tab

See test-case.

I get:
TabView.qml:247: TypeError: Cannot read property '__inserted' of null

followed by a crash if I press a tab.

This happens because gc deleted the tab. The code in TabView.qml looks correct, and gives a parent to tab, so this must be a js engine problem.

I'm only calling gc() explicitly in this test-case, in real life it's being called automatically.

I tried another test-case where I moved gc() outside of the OnCompleted block, into a MouseArea onClicked handler, and I can't reproduce any longer, so it looks like the problem is when gc() is called and we're inside a OnCompleted handler.

Works perfectly with 5.2.1