Evaluated and plain versions of the slot tree key computation function give different results

[gballet]

The evaluated and plain versions of the slot tree key computation function give different results.

That is, the output of GetTreeKeyStorageSlot gives a different result than doing EvaluateAddressPoint first, and then use it to compute the slot key in GetTreeKeyStorageSlotWithEvaluatedAddress. This could come from how the parameters to the first function were calculated. Since other clients find the same value, the plain version is probably the wrong one, but it might be that everyone "fixed" their code when they saw it gave a different result from what geth was giving.