`EscapeInfo` now conforms to the generic protocols defined in `WalkUtils`.
This simplifies the implementation a bit, since trivial instructions are handled
by `WalkUtils` and `EscapeInfo` only has to handle a subset of instructions
inherent to escape information.
Passes using `EscapeInfo` are updated accordingly to become visitors that
customize the `EscapeInfo` walk.
The ComputeEffects pass derives escape information for function arguments and adds those effects in the function.
This needs a lot of changes in check-lines in the tests, because the effects are printed in SIL
The ComputeEffects pass derives escape information for function arguments and adds those effects in the function.
This needs a lot of changes in check-lines in the tests, because the effects are printed in SIL
