Bug 1457635: Remove values::Verbatim. r=xidorn

No point of having two things that do the same.

MozReview-Commit-ID: Do1L4bvOeVQ

servo/components/style_derive/to_css.rs

@@ -175,7 +175,7 @@ fn derive_single_field_expr(
                 {
                     let mut iter = #field.iter().peekable();
                     if iter.peek().is_none() {
-                        writer.item(&::style_traits::values::Verbatim(#if_empty))?;
+                        writer.raw_item(#if_empty)?;
                     } else {
                         for item in iter {
                             writer.item(&item)?;

servo/components/style_traits/values.rs

@@ -235,21 +235,6 @@ where
     }
 }
 
-/// A wrapper type that implements `ToCss` by printing its inner field.
-pub struct Verbatim<'a, T>(pub &'a T)
-where
-    T: ?Sized + 'a;
-
-impl<'a, T> ToCss for Verbatim<'a, T>
-where
-    T: AsRef<str> + ?Sized + 'a,
-{
-    #[inline]
-    fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result where W: Write {
-        dest.write_str(self.0.as_ref())
-    }
-}
-
 /// Type used as the associated type in the `OneOrMoreSeparated` trait on a
 /// type to indicate that a serialized list of elements of this type is
 /// separated by commas.