[llvm] r193412 - Call destroy from ~BasicCallGraph.

[Rafael Espíndola]

> The idea was that a more sophisticated call graph analysis (e.g. based on points-to, or higher level information encoded in metadata) could provide a more refined callgraph.
>
> This dated back to when I was working on DSA.  I don't know of anything that actually used this though, I'd be perfectly fine with merging them together into a single class.

I will give that a try.

Cheers,
Rafael