patch 7.4.1611
Problem: The versplit feature makes the code uneccessary complicated.
Solution: Remove FEAT_VERTSPLIT, always support vertical splits when
FEAT_WINDOWS is defined.
diff --git a/src/gui.h b/src/gui.h
index f119de5..4e557ad 100644
--- a/src/gui.h
+++ b/src/gui.h
@@ -179,7 +179,7 @@
/* Values measured in characters: */
int top; /* Top of scroll bar (chars from row 0) */
int height; /* Current height of scroll bar in rows */
-#ifdef FEAT_VERTSPLIT
+#ifdef FEAT_WINDOWS
int width; /* Current width of scroll bar in cols */
#endif
int status_height; /* Height of status line */