[librsvg: 15/22] Inline WritingMode::is_vertical in its only caller

[Marge Bot <marge-bot src gnome org>]

commit 7c4b607d61b493b84670c69606827c3344a227a5
Author: Federico Mena Quintero <federico gnome org>
Date:   Thu Sep 23 11:09:46 2021 -0500

    Inline WritingMode::is_vertical in its only caller
    
    Part-of: <https://gitlab.gnome.org/GNOME/librsvg/-/merge_requests/593>

 src/property_defs.rs | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)
---
diff --git a/src/property_defs.rs b/src/property_defs.rs
index be1524fc..b1407712 100644
--- a/src/property_defs.rs
+++ b/src/property_defs.rs
@@ -1049,12 +1049,8 @@ make_property!(
 );
 
 impl WritingMode {
-    pub fn is_vertical(self) -> bool {
-        matches!(self, WritingMode::Tb | WritingMode::TbRl)
-    }
-
     pub fn is_horizontal(self) -> bool {
-        !self.is_vertical()
+        !matches!(self, WritingMode::Tb | WritingMode::TbRl)
     }
 }