Broadcasting a StructArray yields a regular array

[Keno]

I feel like this should probably also be a StructArray.

julia> s = StructArray{ComplexF64}((rand(2,2), rand(2,2)))
2×2 StructArray(::Array{Float64,2}, ::Array{Float64,2}) with eltype Complex{Float64}:
 0.838311+0.103134im  0.687063+0.555663im
 0.990479+0.706477im  0.934305+0.885454im

julia> s .+ s
2×2 Array{Complex{Float64},2}:
 1.67662+0.206268im  1.37413+1.11133im
 1.98096+1.41295im   1.86861+1.7709im