khtml uses qx11info_x11 without checking for qtx11support

[Stephen Kelly]

Treeve Jelbert wrote:

> /var/git/kf5/khtml/khtmlview.cpp:36:26: fatal error: qx11info_x11.h: No
> such file or directory
> compilation terminated.
> 
> Also qtx11support is broken, still uses obsolete QT_{BEGIN,END}_HEADER

Please make sure you are using codereview.qt-project.org:qt/qtx11extras.

Thanks,

Steve.