patch 9.0.0639: checking for popup in screen_char() is too late

Problem:    Checking for popup in screen_char() is too late, the attribute has
            already been changed.
Solution:   Move check for popup to where screen_char() is called.

src/version.c

@@ -699,6 +699,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    639,
 /**/
     638,
 /**/