[gnome-builder/wip/gtk4-port] libide/editor: fix precondition check

[Christian Hergert <chergert src gnome org>]

commit e3e1900edcd2c722f0891dc34695a0367dd7777c
Author: Christian Hergert <chergert redhat com>
Date:   Tue Apr 26 17:54:56 2022 -0700

    libide/editor: fix precondition check

 src/libide/editor/ide-editor-page.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/libide/editor/ide-editor-page.c b/src/libide/editor/ide-editor-page.c
index f0edee117..060bbc925 100644
--- a/src/libide/editor/ide-editor-page.c
+++ b/src/libide/editor/ide-editor-page.c
@@ -755,7 +755,7 @@ ide_editor_page_set_gutter (IdeEditorPage *self,
   IDE_ENTRY;
 
   g_return_if_fail (IDE_IS_EDITOR_PAGE (self));
-  g_return_if_fail (!gutter || IDE_IS_GUTTER (self));
+  g_return_if_fail (!gutter || IDE_IS_GUTTER (gutter));
 
   if (gutter == self->gutter)
     IDE_EXIT;