fix!: make :undo! notify buffer update callbacks (#20344)

When :undo! was introduced to Nvim the implementation of 'inccommand'
preview callback hasn't been fully decided yet, so not notifying buffer
update callbacks made sense for 'inccommand' preview callback in case it
needs to undo the changes itself.
Now it turns out that the undo-and-forget is done automatically for
'inccommand', so it doesn't make sense for :undo! to avoid notifying
buffer update callbacks anymore.

1 files changed, 2 insertions, 2 deletions

diff --git a/src/nvim/ex_docmd.c b/src/nvim/ex_docmd.c
index 085948f7b1..7ece195374 100644
--- a/src/nvim/ex_docmd.c
+++ b/src/nvim/ex_docmd.c
@@ -5867,7 +5867,7 @@ static void ex_undo(exarg_T *eap)
 {
   if (eap->addr_count != 1) {
     if (eap->forceit) {
-      u_undo_and_forget(1);         // :undo!
+      u_undo_and_forget(1, true);   // :undo!
     } else {
       u_undo(1);                    // :undo
     }
@@ -5894,7 +5894,7 @@ static void ex_undo(exarg_T *eap)
       emsg(_(e_undobang_cannot_redo_or_move_branch));
       return;
     }
-    u_undo_and_forget(count);
+    u_undo_and_forget(count, true);
   } else {                        // :undo 123
     undo_time(step, false, false, true);
   }