gdiplus: Added GdipSetPenLineJoin.
diff --git a/include/gdiplusflat.h b/include/gdiplusflat.h
index 4e5e95f..5e275c9 100644
--- a/include/gdiplusflat.h
+++ b/include/gdiplusflat.h
@@ -30,6 +30,7 @@
 GpStatus WINGDIPAPI GdipCreatePen1(ARGB,REAL,GpUnit,GpPen**);
 GpStatus WINGDIPAPI GdipDeletePen(GpPen*);
 GpStatus WINGDIPAPI GdipSetPenEndCap(GpPen*,GpLineCap);
+GpStatus WINGDIPAPI GdipSetPenLineJoin(GpPen*,GpLineJoin);
 
 GpStatus WINGDIPAPI GdipCreateFromHDC(HDC,GpGraphics**);
 GpStatus WINGDIPAPI GdipCreateFromHWND(HWND,GpGraphics**);