Regression in Fusion when using smaller fonts

openSUSE 13.2, using 141dpi 15" laptop and 169dpi 13" laptop, both native resolution/dpi, both configured to use 6pt font. After updating from 5.3.2 to 5.4.0 some widgets are drown wrongly:

• checkboxes
• radio
• tab bar
• menu items for checkbox and radio

On normal layouts checkboxes and radio are just out of proportion, but in menus the checkboxes and radios are not fitting the size of menu item, and drawing some strange artifact instead. Please see the attached screenshots.

Console output:

user@thinkpad:~> xdpyinfo | grep -A1 'dimensions'
  dimensions:    1920x1080 pixels (345x194 millimeters)
  resolution:    141x141 dots per inch

After debugging the Qt sources, the critical change point is this, when value of 14px transformed into 20px:
https://qt.gitorious.org/qt/qtbase/source/68676d2128e86bbe5c650b8be7f8b78cb7f60e8f:src/widgets/styles/qfusionstyle.cpp#L3126
Minimal reproducer application attached as well.

It would be amazing if those widgets would scale depending on the size of the text, but better to keep them smaller with big text than huge with smaller text.