Variable overflow in QWidgetItemV2

Repeated calls to

QWidgetItemV2::heightForWidth(int width)

(e.g. in a UI that is constantly updating) lead to an overflow of

QWidgetItemV2::q_firstCachedHfw

 resulting in a negative index into

q_cachedHfws

and subsequent memory corruption.

See: https://code.qt.io/cgit/qt/qtbase.git/tree/src/widgets/kernel/qlayoutitem.h?h=v6.1.0-rc1&id=c7deb3400faa1d9389137fe63ffbffade8203850#n170

Recommend to change datatype of

QWidgetItemV2::q_firstCachedHfw

to

unsigned short

This also applies to the local variable

int offset

https://code.qt.io/cgit/qt/qtbase.git/tree/src/widgets/kernel/qlayoutitem.cpp?h=v6.1.0-rc1&id=c7deb3400faa1d9389137fe63ffbffade8203850#n849

A change to

unsigned short

would be good.