[LyX/master] Update correctly completion after undo

[Jean-Marc Lasgouttes]

commit 06acb7f806f99cd418781f9d0645b213f8241062
Author: Jean-Marc Lasgouttes <lasgouttes at lyx.org>
Date:   Thu Oct 14 16:39:33 2021 +0200

    Update correctly completion after undo
    
    This is take #2 after reverting e59aee458.
    
    Request the completer to rebuild a completion after undo/redo.
    
    Fixes #12383.
---
 src/frontends/qt/GuiView.cpp |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/src/frontends/qt/GuiView.cpp b/src/frontends/qt/GuiView.cpp
index 767791f..9126d48 100644
--- a/src/frontends/qt/GuiView.cpp
+++ b/src/frontends/qt/GuiView.cpp
@@ -4067,8 +4067,10 @@ void GuiView::dispatchToBufferView(FuncRequest const & cmd, DispatchResult & dr)
 	// Let the current BufferView dispatch its own actions.
 	bv->dispatch(cmd, dr);
 	if (dr.dispatched()) {
-		if (cmd.action() == LFUN_REDO || cmd.action() == LFUN_UNDO)
+		if (cmd.action() == LFUN_REDO || cmd.action() == LFUN_UNDO) {
+			updateCompletion(bv->cursor(), true, false);
 			updateDialog("document", "");
+		}
 		return;
 	}