[devtools] CWTC.request is gone, don't attempt to use it in CWTC.view
So one will have to provide at least one of `rset` or `req` argument of the `view`
method.
[devtools] Handle i18ncube command for "cubes as packages"
And add a test so that both layouts are tested.
Move the test cube into a package.
Related to #13001466.