Turned QStyleOptionViewItem into value type, for it has a public copy constructor.
Turned QStyleOptionViewItem into value type, for it has a public copy constructor.

It is passed around by value in many places, like the return value of
QAbstractItemView::viewOptions(). I did the same to the variations:
QStyleOptionViewItemV2, QStyleOptionViewItemV3, etc.

gbaty/pyside2,qtproject/pyside-pyside,pankajp/pyside,M4rtinK/pyside-bb10,pankajp/pyside,IronManMark20/pyside2,M4rtinK/pyside-bb10,IronManMark20/pyside2,PySide/PySide,enthought/pyside,gbaty/pyside2,M4rtinK/pyside-android,BadSingleton/pyside2,qtproject/pyside-pyside,qtproject/pyside-pyside,M4rtinK/pyside-android,M4rtinK/pyside-bb10,BadSingleton/pyside2,IronManMark20/pyside2,RobinD42/pyside,qtproject/pyside-pyside,RobinD42/pyside,M4rtinK/pyside-bb10,M4rtinK/pyside-android,pankajp/pyside,RobinD42/pyside,RobinD42/pyside,BadSingleton/pyside2,BadSingleton/pyside2,enthought/pyside,pankajp/pyside,BadSingleton/pyside2,M4rtinK/pyside-android,PySide/PySide,enthought/pyside,PySide/PySide,gbaty/pyside2,gbaty/pyside2,M4rtinK/pyside-android,PySide/PySide,enthought/pyside,enthought/pyside,pankajp/pyside,enthought/pyside,enthought/pyside,RobinD42/pyside,RobinD42/pyside,M4rtinK/pyside-android,IronManMark20/pyside2,RobinD42/pyside,gbaty/pyside2,PySide/PySide,M4rtinK/pyside-bb10,qtproject/pyside-pyside,M4rtinK/pyside-bb10,IronManMark20/pyside2