diff -up thunderbird-60.5.3/servo/components/style_traits/values.rs.rust-1.33-build thunderbird-60.5.3/servo/components/style_traits/values.rs
--- thunderbird-60.5.3/servo/components/style_traits/values.rs.rust-1.33-build	2019-03-04 19:17:27.000000000 +0100
+++ thunderbird-60.5.3/servo/components/style_traits/values.rs	2019-03-12 12:10:04.596635368 +0100
@@ -135,24 +135,6 @@ where
     }
 }
 
-#[macro_export]
-macro_rules! serialize_function {
-    ($dest: expr, $name: ident($( $arg: expr, )+)) => {
-        serialize_function!($dest, $name($($arg),+))
-    };
-    ($dest: expr, $name: ident($first_arg: expr $( , $arg: expr )*)) => {
-        {
-            $dest.write_str(concat!(stringify!($name), "("))?;
-            $first_arg.to_css($dest)?;
-            $(
-                $dest.write_str(", ")?;
-                $arg.to_css($dest)?;
-            )*
-            $dest.write_char(')')
-        }
-    }
-}
-
 /// Convenience wrapper to serialise CSS values separated by a given string.
 pub struct SequenceWriter<'a, 'b: 'a, W: 'b> {
     inner: &'a mut CssWriter<'b, W>,
@@ -404,7 +386,7 @@ impl_to_css_for_predefined_type!(::csspa
 impl_to_css_for_predefined_type!(::cssparser::Color);
 impl_to_css_for_predefined_type!(::cssparser::UnicodeRange);
 
-#[macro_export]
+/// Define an enum type with unit variants that each correspond to a CSS keyword.
 macro_rules! define_css_keyword_enum {
     (pub enum $name:ident { $($variant:ident = $css:expr,)+ }) => {
         #[allow(missing_docs)]