Tests that plug-ins can query for the contents scale factor

On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".


PASS plugin1.contentsScaleFactor is 1.0
PASS plugin1.cachedContentsScaleFactor is 1.0
PASS plugin1.contentsScaleFactor is 2.0
PASS plugin1.cachedContentsScaleFactor is 2.0
PASS plugin2.contentsScaleFactor is 2.0
PASS plugin2.cachedContentsScaleFactor is 2.0