Mac QSystemTrayIcon scaling not retina-aware (and also wrong)

Search for "qt_mac_create_nsimage" in "qsystemtrayicon_mac.cpp" and you will find multiple locations where it scales the icon to "scale x scale" where "scale" is "[[[NSApplication sharedApplication] mainMenu] menuBarHeight] - 4".

This value does not depend on the pixel scale factor, so we get low-res icons on retina capable systems, even though we supply high resolution icons.

Also it is less than ideal to scale it to a square with sides equal to the menu bar height (minus 4), since icons on mac can typically be rectangular. In particular, I have pixel perfect icons designed for mac, and would like them to be used 1:1.

I wish there was a virtual method or something I could override in QSystemTrayIcon to get get my wanted (correct) behavior, while the default could implement the backward compatible behavior.

By the way, I can not find "qsystemtrayicon_mac.cpp" in the Qt 5.1.1 sources (qt-everywhere-opensource-src-5.1.1), so I don't know whether it's affected.