QVectorND, QQuaternion, and QColor all operate on floats rather than
qreal or double, so explicit use float literals in the tests.
Pick-to: 6.1
Change-Id: If12cc12ddd9cd8219f3d78bf24e1400921e26c2b
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>