https://github.com/dotnet/roslyn/blob/master/src/Compilers/CSharp/Portable/Operations/CSharpOperationFactory.cs#L321

This captures the boundNode element in the lambda for getChildren, and it doesn't need to. We should update this to be non-capturing.

I'm going to mark this up for grabs so that anyone in the community who would like to make a small improvement can do so, as I am focusing on the nullable api at the moment. If no has taken this up after that work is completed, I'll probably fix this.