[gnome-builder] sourceview: fix possible negative value for margin

[Christian Hergert <chergert src gnome org>]

commit 2de607598a07ee9727279161a59be94f2bb7a322
Author: Christian Hergert <chergert redhat com>
Date:   Tue Mar 26 17:54:29 2019 -0700

    sourceview: fix possible negative value for margin

 src/libide/sourceview/ide-source-view.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/libide/sourceview/ide-source-view.c b/src/libide/sourceview/ide-source-view.c
index 3beeefb62..a7444d711 100644
--- a/src/libide/sourceview/ide-source-view.c
+++ b/src/libide/sourceview/ide-source-view.c
@@ -3821,7 +3821,7 @@ ide_source_view_set_overscroll_num_lines (IdeSourceView *self,
         new_margin = height - priv->cached_char_height;
     }
 
-  new_margin = CLAMP (new_margin, 0, height - priv->cached_char_height);
+  new_margin = CLAMP (new_margin, 0, MAX (height - priv->cached_char_height, 0));
 
   g_object_set (self,
                 "bottom-margin", new_margin,