Fixed closing sub-path of wxGraphicsPath with GDI+ renderer.

Close sub-path only if it is really open.

src/msw/graphics.cpp

@@ -1227,6 +1227,8 @@ void wxGDIPlusPathData::AddLineToPoint( wxDouble x , wxDouble y )
 
 void wxGDIPlusPathData::CloseSubpath()
 {
+    if( m_figureOpened )
+    {
         m_path->CloseFigure();
         m_figureOpened = false;
         // Since native GDI+ renderer doesn't move its current point
@@ -1234,6 +1236,7 @@ void wxGDIPlusPathData::CloseSubpath()
         // it on our own in this case.
         m_logCurrentPoint = m_figureStart;
         m_logCurrentPointSet = true;
+    }
 }
 
 void wxGDIPlusPathData::AddCurveToPoint( wxDouble cx1, wxDouble cy1, wxDouble cx2, wxDouble cy2, wxDouble x, wxDouble y )