[gnome-builder/wip/gtk4-port: 676/736] libide/code: be more defensive against missing style

[Christian Hergert <chergert src gnome org>]

commit 95d4eb70b7b920d9e29bfb1ed454e4fce238018f
Author: Christian Hergert <chergert redhat com>
Date:   Wed Apr 20 12:13:26 2022 -0700

    libide/code: be more defensive against missing style

 src/libide/code/ide-highlight-engine.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)
---
diff --git a/src/libide/code/ide-highlight-engine.c b/src/libide/code/ide-highlight-engine.c
index 3964600ab..9b96d2aaa 100644
--- a/src/libide/code/ide-highlight-engine.c
+++ b/src/libide/code/ide-highlight-engine.c
@@ -172,9 +172,8 @@ sync_tag_style (GtkSourceStyleScheme *style_scheme,
   style_name = tag_name;
 
   /*
-   * Check if this is a private tag.A tag is private if it starts with
-   * PRIVATE_TAG_PREFIX "Builder".
-   * ex: Builder:c:boolean
+   * Check if this is a private tag. A tag is private if it starts with
+   * PRIVATE_TAG_PREFIX "Builder" such as "Builder:c:boolean".
    * If the tag is private extract the original style name by moving the string
    * strlen (PRIVATE_TAG_PREFIX) + 1 (the colon) characters.
    */
@@ -193,6 +192,9 @@ sync_tag_style (GtkSourceStyleScheme *style_scheme,
         }
     }
 
+  if (style == NULL)
+    return;
+
   g_object_get (style,
                 "background", &background,
                 "background-set", &background_set,