Previously the test consisted of just one cpp file. An attempt to add
more test cases to the file resulted in the minGW compiler complaining
about a too large object file:
Fatal error: tst_qcomparehelpers.cpp.obj: file too big
This patch splits the implementation into a header and a cpp file.
This itself does not fix the issues, but now we can add the new test
cases in a separate cpp file. This patch also adds some comments
that advocate doing so.
Pick-to: 6.7
Change-Id: I451987370fa4e18b7ad81dfc064ea016f1d0da47
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
e26914fa0f