Previous setup of the test was failing in minimal static build if built
using the unity build because of the explicit inclusion of the qtcore
source files. By removing them, it surfaced that QFileSystemEntry
doesn't export all its necessary symbols for testing. So this patch does
that, as well as removing the qtcore sources from the test. It also
makes sense to make the test private.
Pick-to: 6.5
Task-number: QTBUG-109394
Change-Id: Icdabe32485b7ce4ed6049bcc24918f531406b4bd
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
11ae4b70a1