Don't draw the segment lines in wxGtkPrinterDC::DrawArc() unless it's filled.

The segments should only be drawn if we're filling the arc, i.e. drawing a
pie, but not if we're just drawing its outline.

Add a test of this to the printing sample.

Closes #15609.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@75065 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

samples/printing/printing.cpp

@@ -182,6 +182,12 @@ void MyApp::Draw(wxDC&dc)
     dc.DrawPolygon( 5, points, 20, 250, wxODDEVEN_RULE );
     dc.DrawPolygon( 5, points, 50, 250, wxWINDING_RULE );
 
+    dc.DrawArc( 20, 330, 40, 300, 20, 300 );
+    {
+        wxDCBrushChanger changeBrush(dc, *wxTRANSPARENT_BRUSH);
+        dc.DrawArc( 60, 330, 80, 300, 60, 300 );
+    }
+
     dc.DrawEllipticArc( 80, 250, 60, 30, 0.0, 270.0 );
 
     points[0].x = 150;
@@ -194,8 +200,6 @@ void MyApp::Draw(wxDC&dc)
     points[3].y = 220;
     dc.DrawSpline( 4, points );
 
-    dc.DrawArc( 20,10, 10,10, 25,40 );
-
     wxString str;
     int i = 0;
     str.Printf( wxT("---- Text at angle %d ----"), i );