patch 8.1.0527: using 'shiftwidth' from wrong buffer for folding

Problem:    Using 'shiftwidth' from wrong buffer for folding.
Solution:   Use "buf" instead of "curbuf". (Christian Brabandt)

src/version.c

@@ -792,6 +792,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    527,
 /**/
     526,
 /**/