Lists: Fix handling of go arrays

[alvaroaleman]

Go arrays currently cause a panic, because reflect.MakeSlice is used to construct them which is invalid, this change fixes that.

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[TristonianJones]

/gcbrun

[alvaroaleman]

Had to rebase to fix some conflicts, please take another look when you can.

[TristonianJones]

/gcbrun