It's used by the lancebench and the lance tool, and it will probably be
useful for writing some high-dpi related unit and baseline test cases,
so move it to the shared folder.
Change-Id: I969bab51c9504be13b4c192b4f29f69cd9102868
Reviewed-by: Eirik Aavitsland <eirik.aavitsland@qt.io>