Test basic inheritance
Test relative unit (em).
Resolved to absolute value?
Test percentage resolution.
Resolved to absolute value?
Test smaller font-size.
Test larger font-size.
Test smaller than a percentage font-size.
Computation (see org.apache.fop.fo.properties.FontSizePropertyMaker):
12pt * 80% = 9,6pt (base-size)
9,6pt < 12pt, so scale is 10/12
12 * 10/12 = 9,99pt, still > 9,6pt
9,99pt * 10/12 = 8,33pt STOP