Add a test for GetCurrentObject, make it pass under Wine.

diff --git a/include/wingdi.h b/include/wingdi.h
index ed6d4ca..0d86ebf 100644
--- a/include/wingdi.h
+++ b/include/wingdi.h
@@ -3385,6 +3385,7 @@
 INT         WINAPI GetClipBox(HDC,LPRECT);
 INT         WINAPI GetClipRgn(HDC,HRGN);
 BOOL        WINAPI GetColorAdjustment(HDC, LPCOLORADJUSTMENT);
+HCOLORSPACE WINAPI GetColorSpace(HDC);
 HGDIOBJ     WINAPI GetCurrentObject(HDC,UINT);
 BOOL        WINAPI GetCurrentPositionEx(HDC,LPPOINT);
 INT         WINAPI GetDeviceCaps(HDC,INT);