[llvm] r184217 - Add a GetUniqueID that will replace the uniqueID of PathV1.h.

[Rafael Espíndola]

> Ask and you shall receive.  ;-)
>
> I chose to friend GetUniqueID instead of replicate the logic from
> status, which hopefully is not too problematic.  Also, I added unit
> tests for this, since it appears to be entirely untested (aside from
> usage).

Awesome!

LGTM.

> ~Aaron

Cheers,
Rafael