`make check' breaks on mac for testcases with CONFIG+=qmltestcase and CONFIG+=testcase

On mac, if a testcase adds both "qmltestcase" and "testcase" to CONFIG, and qmltestcase.prf is loaded after testcase.prf, then the testcase is not built as app bundle but `make check' attempts to run it as if it is.

The reason is that qmltestcase.prf contains this:

macx: CONFIG -= app_bundle

... and testcase.prf checks contains(CONFIG,app_bundle) to determine the correct command to run.
Therefore changing app_bundle after loading testcase.prf will break the "check" target.

Workarounds are either doing CONFIG -= app_bundle in the affected test .pro file, or avoiding CONFIG += testcase and only using CONFIG += qmltestcase for qml tests.

I'm not sure why qmltestcase.prf is doing CONFIG -= app_bundle. It's possible that should be removed. If not, the load order needs to be enforced somehow.