ASTProviderTest is hanging

I noticed that recent PR runs are failing and when I traced a console run, it was stuck in ASTProviderTest. When I run ASTProviderTest locally, it hangs for over 48 mins before I kill it. I tried backing off a number of patches that might be suspect such as @fedejeanne 's cancellable AST patch, but it does not make a difference. I also backed off a number of recent jdt.core patches to a few days ago and still the same result.