[gtk/wip/carlosg/im-wayland-backports-3.24: 3/3] imcontextwayland: Ignore preedit updates from NULL to NULL

[Carlos Garnacho <carlosg src gnome org>]

commit 5321fa25a52f9d91ed0c2f5ec59afbd8fd2f770a
Author: Carlos Garnacho <carlosg gnome org>
Date:   Tue Apr 26 12:23:09 2022 +0200

    imcontextwayland: Ignore preedit updates from NULL to NULL
    
    If we get consecutive preedit string updates that announce a NULL
    string, we still do end up issuing ::preedit-changed with those.
    Ignore changes from NULL to NULL, it is the other combinations which
    must issue this signal.

 modules/input/imwayland.c | 3 +++
 1 file changed, 3 insertions(+)
---
diff --git a/modules/input/imwayland.c b/modules/input/imwayland.c
index 9b738208d9..1e93123aa2 100644
--- a/modules/input/imwayland.c
+++ b/modules/input/imwayland.c
@@ -171,6 +171,9 @@ text_input_preedit_apply (GtkIMContextWaylandGlobal *global)
     return;
 
   context = GTK_IM_CONTEXT_WAYLAND (global->current);
+  if (context->pending_preedit.text == NULL &&
+      context->current_preedit.text == NULL)
+    return;
 
   state_change = ((context->pending_preedit.text == NULL)
                  != (context->current_preedit.text == NULL));