Don't use possibly uninitialized pen in wxMSWDCImpl.

Check that m_pen is valid before checking if it is transparent in
DoDrawRoundedRectangle() too (this was already done in DoDrawRectangle() in
r53150).

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@62288 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/msw/dc.cpp

@@ -965,7 +965,7 @@ void wxMSWDCImpl::DoDrawRoundedRectangle(wxCoord x, wxCoord y, wxCoord width, wx
     // Windows draws the filled rectangles without outline (i.e. drawn with a
     // transparent pen) one pixel smaller in both directions and we want them
     // to have the same size regardless of which pen is used - adjust
-    if ( m_pen.GetStyle() == wxPENSTYLE_TRANSPARENT )
+    if ( m_pen.IsOk() && m_pen.GetStyle() == wxPENSTYLE_TRANSPARENT )
     {
         x2++;
         y2++;