bug#31643: Scribus fails to build since Qt upgrade

[Ricardo Wurmus]

Scribus fails to build, probably because of the Qt upgrade.  There are a
bunch of errors; some of them are reproduced here:

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…
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/2geomtools/meshdistortion/meshdistortiondialog.cpp:58:12:
 error: invalid use of incomplete type ‘const class QStyleOptionGraphicsItem’
  if (option->state & QStyle::State_Selected)
            ^
In file included from 
/gnu/store/xgpwah2hppghgc7c09jp643ddm2lfjj5-qtbase-5.11.0/include/qt5/QtWidgets/QGraphicsEllipseItem:1:0,
                 from 
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/2geomtools/meshdistortion/meshdistortiondialog.h:32,
                 from 
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/2geomtools/meshdistortion/meshdistortiondialog.cpp:27:
/gnu/store/xgpwah2hppghgc7c09jp643ddm2lfjj5-qtbase-5.11.0/include/qt5/QtWidgets/qgraphicsitem.h:80:7:
 note: forward declaration of ‘class QStyleOptionGraphicsItem’
 class QStyleOptionGraphicsItem;
       ^
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/2geomtools/meshdistortion/meshdistortiondialog.cpp:58:22:
 error: incomplete type ‘QStyle’ used in nested name specifier
  if (option->state & QStyle::State_Selected)
                      ^
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/2geomtools/meshdistortion/meshdistortiondialog.cpp:61:55:
 error: invalid use of incomplete type ‘const class QStyleOptionGraphicsItem’
   painter->setPen(QPen(Qt::red, qMax(0.1, 1.0 / option->levelOfDetail)));
                                                       ^
In file included from 
/gnu/store/xgpwah2hppghgc7c09jp643ddm2lfjj5-qtbase-5.11.0/include/qt5/QtWidgets/QGraphicsEllipseItem:1:0,
                 from 
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/2geomtools/meshdistortion/meshdistortiondialog.h:32,
                 from 
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/2geomtools/meshdistortion/meshdistortiondialog.cpp:27:
/gnu/store/xgpwah2hppghgc7c09jp643ddm2lfjj5-qtbase-5.11.0/include/qt5/QtWidgets/qgraphicsitem.h:80:7:
 note: forward declaration of ‘class QStyleOptionGraphicsItem’
 class QStyleOptionGraphicsItem;
       ^
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/2geomtools/meshdistortion/meshdistortiondialog.cpp:66:55:
 error: invalid use of incomplete type ‘const class QStyleOptionGraphicsItem’
   painter->setPen(QPen(Qt::red, qMax(0.2, 2.0 / option->levelOfDetail)));
                                                       ^
In file included from 
/gnu/store/xgpwah2hppghgc7c09jp643ddm2lfjj5-qtbase-5.11.0/include/qt5/QtWidgets/QGraphicsEllipseItem:1:0,
                 from 
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/2geomtools/meshdistortion/meshdistortiondialog.h:32,
                 from 
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/2geomtools/meshdistortion/meshdistortiondialog.cpp:27:
/gnu/store/xgpwah2hppghgc7c09jp643ddm2lfjj5-qtbase-5.11.0/include/qt5/QtWidgets/qgraphicsitem.h:80:7:
 note: forward declaration of ‘class QStyleOptionGraphicsItem’
 class QStyleOptionGraphicsItem;
       ^
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/lenseffects/lensdialog.cpp:
 In member function ‘virtual void LensItem::paint(QPainter*, const 
QStyleOptionGraphicsItem*, QWidget*)’:
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/lenseffects/lensdialog.cpp:58:46:
 error: invalid use of incomplete type ‘const class QStyleOptionGraphicsItem’
  painter->setPen(QPen(Qt::black, 1.0 / option->levelOfDetail));
                                              ^
In file included from 
/gnu/store/xgpwah2hppghgc7c09jp643ddm2lfjj5-qtbase-5.11.0/include/qt5/QtWidgets/QGraphicsItem:1:0,
                 from 
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/lenseffects/lensdialog.h:33,
                 from 
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/lenseffects/lensdialog.cpp:27:
/gnu/store/xgpwah2hppghgc7c09jp643ddm2lfjj5-qtbase-5.11.0/include/qt5/QtWidgets/qgraphicsitem.h:80:7:
 note: forward declaration of ‘class QStyleOptionGraphicsItem’
 class QStyleOptionGraphicsItem;
       ^
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/lenseffects/lensdialog.cpp:66:12:
 error: invalid use of incomplete type ‘const class QStyleOptionGraphicsItem’
  if (option->state & QStyle::State_Selected)
            ^
In file included from 
/gnu/store/xgpwah2hppghgc7c09jp643ddm2lfjj5-qtbase-5.11.0/include/qt5/QtWidgets/QGraphicsItem:1:0,
                 from 
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/lenseffects/lensdialog.h:33,
                 from 
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/lenseffects/lensdialog.cpp:27:
/gnu/store/xgpwah2hppghgc7c09jp643ddm2lfjj5-qtbase-5.11.0/include/qt5/QtWidgets/qgraphicsitem.h:80:7:
 note: forward declaration of ‘class QStyleOptionGraphicsItem’
 class QStyleOptionGraphicsItem;
       ^
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/lenseffects/lensdialog.cpp:66:22:
 error: incomplete type ‘QStyle’ used in nested name specifier
  if (option->state & QStyle::State_Selected)
                      ^
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/lenseffects/lensdialog.cpp:68:19:
 error: invalid use of incomplete type ‘const class QStyleOptionGraphicsItem’
   scaling = option->levelOfDetail;
                   ^
In file included from 
/gnu/store/xgpwah2hppghgc7c09jp643ddm2lfjj5-qtbase-5.11.0/include/qt5/QtWidgets/QGraphicsItem:1:0,
                 from 
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/lenseffects/lensdialog.h:33,
                 from 
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/lenseffects/lensdialog.cpp:27:
/gnu/store/xgpwah2hppghgc7c09jp643ddm2lfjj5-qtbase-5.11.0/include/qt5/QtWidgets/qgraphicsitem.h:80:7:
 note: forward declaration of ‘class QStyleOptionGraphicsItem’
 class QStyleOptionGraphicsItem;
       ^
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/lenseffects/lensdialog.cpp:69:28:
 error: invalid use of incomplete type ‘const class QStyleOptionGraphicsItem’
   double siz = 6.0 / option->levelOfDetail;
                            ^
In file included from 
/gnu/store/xgpwah2hppghgc7c09jp643ddm2lfjj5-qtbase-5.11.0/include/qt5/QtWidgets/QGraphicsItem:1:0,
                 from 
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/lenseffects/lensdialog.h:33,
                 from 
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/lenseffects/lensdialog.cpp:27:
/gnu/store/xgpwah2hppghgc7c09jp643ddm2lfjj5-qtbase-5.11.0/include/qt5/QtWidgets/qgraphicsitem.h:80:7:
 note: forward declaration of ‘class QStyleOptionGraphicsItem’
 class QStyleOptionGraphicsItem;
       ^
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/lenseffects/lensdialog.cpp:72:45:
 error: invalid use of incomplete type ‘const class QStyleOptionGraphicsItem’
   painter->setPen(QPen(Qt::red, 1.0 / option->levelOfDetail, Qt::DotLine));
                                             ^
In file included from 
/gnu/store/xgpwah2hppghgc7c09jp643ddm2lfjj5-qtbase-5.11.0/include/qt5/QtWidgets/QGraphicsItem:1:0,
                 from 
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/lenseffects/lensdialog.h:33,
                 from 
/tmp/guix-build-scribus-1.5.3.drv-0/scribus-1.5.3/scribus/plugins/tools/lenseffects/lensdialog.cpp:27:
/gnu/store/xgpwah2hppghgc7c09jp643ddm2lfjj5-qtbase-5.11.0/include/qt5/QtWidgets/qgraphicsitem.h:80:7:
 note: forward declaration of ‘class QStyleOptionGraphicsItem’
 class QStyleOptionGraphicsItem;
       ^
make[2]: *** 
[scribus/plugins/tools/2geomtools/meshdistortion/CMakeFiles/meshdistortion.dir/build.make:77:
 
scribus/plugins/tools/2geomtools/meshdistortion/CMakeFiles/meshdistortion.dir/meshdistortiondialog.cpp.o]
 Error 1
make[2]: *** Waiting for unfinished jobs....
…
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--
Ricardo