test_one_cmdline() did not check the last parameter.

Reported by Eduard Munteanu.

gdiplus: Workaround missing support for true floating point regions in Wine gdiplus by using a scaling world transform.

This simplifies the test and makes sure that there is no broken workarounds
in the tests.

gdiplus: Detect broken GdipMeasureCharacterRanges behaviour before performing the font height scaling test.