Error when summing view of StrideArray

I am getting the following error when summing over a view:

```repl
julia> using StrideArrays

julia> zeros_sa(size...) = StrideArray(zeros(Float32, size...), static.(size));

julia> A = zeros_sa(10, 10);

julia> sum(A)
0.0f0

julia> sum(view(A, :, :))
0.0f0

julia> sum(view(A, static(1):static(2), :))
ERROR: MethodError: no method matching iterate(::Nothing)
[...]
```