QML uses qPrintable() instead of qUtf8Printable() to display errors

qqmlengine.cpp dumpwarning() uses qPrintable, which contains toLocal8Bit() inside, but QDebug operator<< calls QString::fromUtf8() to convert it back to QString, so it loses some characters like °, and we see � instead. Docs (https://doc.qt.io/qt-5/qtglobal.html#qPrintable) have a note about that.