In this case the srb represents the layout only, and can still be used
to create a pipeline. For setShaderResources() one will then need to use
another, layout compatible, srb that references valid resources.
Change-Id: I3ea5b63df3be8847540ca4c0c40fbd29dbed8fb7
Reviewed-by: Paul Lemire <paul.lemire@kdab.com>
Reviewed-by: Andy Nichols <andy.nichols@qt.io>