Big update to remove deprecation warning from Qt 5.15.0

That is need on MacOS build as travis log is bigger than 50k lines
which breaks travis rules
And by the way deprecations are real
All file contains the same modification replace 0 to Qt::WindowFlags() when needed
as the class needs to be instantiated

Signed-off-by: vejmarie <jmverdun3@gmail.com>

src/Mod/Drawing/Gui/DrawingView.cpp

@@ -463,7 +463,7 @@ void DrawingView::onRelabel(Gui::Document *pDoc)
 
 void DrawingView::printPdf()
 {
-    Gui::FileOptionsDialog dlg(this, 0);
+    Gui::FileOptionsDialog dlg(this, Qt::WindowFlags());
     dlg.setFileMode(QFileDialog::AnyFile);
     dlg.setAcceptMode(QFileDialog::AcceptSave);
     dlg.setWindowTitle(tr("Export PDF"));