vim-patch:7.4.646 #2926

Problem:    ":bufdo" may start at a deleted buffer.
Solution:   Find the first not deleted buffer. (Shane Harper)

https://github.com/vim/vim/commit/v7-4-646

src/nvim/version.c

@@ -163,7 +163,7 @@ static int included_patches[] = {
   //649,
   //648 NA
   //647 NA
-  //646,
+  646,
   //645,
   //644 NA
   //643,