patch 7.4.857
Problem:    Dragging the current tab with the mouse doesn't work properly.
Solution:   Take the current tabpage index into account. (Hirohito Higashi)
diff --git a/src/version.c b/src/version.c
index a3b567e..3fb4ad2 100644
--- a/src/version.c
+++ b/src/version.c
@@ -742,6 +742,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    857,
+/**/
     856,
 /**/
     855,