add the wxFont(const wxSize& pixelSize, ...) ctor to all ports; add some wxCHECK_MSGs to ensure that the wxSize objects contains non-negative arguments; document that passing zero for the width parameter is allowed; other minor doc fixes

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@59564 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/gtk/dcclient.cpp

@@ -1781,7 +1781,7 @@ wxCoord wxWindowDCImpl::GetCharHeight() const
     wxCHECK_MSG( metrics, -1, _T("failed to get pango font metrics") );
 
     wxCoord h = PANGO_PIXELS (pango_font_metrics_get_descent (metrics) +
-                pango_font_metrics_get_ascent (metrics));
+                              pango_font_metrics_get_ascent (metrics));
     pango_font_metrics_unref (metrics);
     return h;
 }