style: Use more Box<[]> and Box<str> for quotes.

components/layout/generated_content.rs

@@ -311,9 +311,9 @@ impl<'a, 'b> ResolveGeneratedContentFragmentMutator<'a, 'b> {
                 &quotes.0[self.traversal.quote as usize]
             };
         if close {
-            close_quote.clone()
+            close_quote.to_string()
         } else {
-            open_quote.clone()
+            open_quote.to_string()
         }
     }
 }

components/style/properties/gecko.mako.rs

@@ -4229,8 +4229,11 @@ fn static_assert() {
             let ref gecko_quote_values = *self.gecko.mQuotes.mRawPtr;
             longhands::quotes::computed_value::T(
                 gecko_quote_values.mQuotePairs.iter().map(|gecko_pair| {
-                    (gecko_pair.first.to_string(), gecko_pair.second.to_string())
-                }).collect()
+                    (
+                        gecko_pair.first.to_string().into_boxed_str(),
+                        gecko_pair.second.to_string().into_boxed_str(),
+                    )
+                }).collect::<Vec<_>>().into_boxed_slice()
             )
         }
     }

components/style/values/computed/list.rs

@@ -7,12 +7,20 @@
 pub use values::specified::list::Quotes;
 
 impl Quotes {
-    /// Initial value for `quotes`
+    /// Initial value for `quotes`.
+    ///
+    /// FIXME(emilio): This should ideally not allocate.
     #[inline]
     pub fn get_initial_value() -> Quotes {
         Quotes(vec![
-            ("\u{201c}".to_owned(), "\u{201d}".to_owned()),
-            ("\u{2018}".to_owned(), "\u{2019}".to_owned()),
-        ])
+            (
+                "\u{201c}".to_owned().into_boxed_str(),
+                "\u{201d}".to_owned().into_boxed_str(),
+            ),
+            (
+                "\u{2018}".to_owned().into_boxed_str(),
+                "\u{2019}".to_owned().into_boxed_str(),
+            ),
+        ].into_boxed_slice())
     }
 }

components/style/values/computed/mod.rs

@@ -401,6 +401,7 @@ trivial_to_computed_value!(BorderStyle);
 trivial_to_computed_value!(Cursor);
 trivial_to_computed_value!(Namespace);
 trivial_to_computed_value!(String);
+trivial_to_computed_value!(Box<str>);
 
 /// A `<number>` value.
 pub type Number = CSSFloat;

components/style/values/specified/list.rs

@@ -4,31 +4,38 @@
 
 //! `list` specified values.
 
-use cssparser::{Parser, Token, serialize_string};
+use cssparser::{Parser, Token};
 use parser::{Parse, ParserContext};
 use std::fmt;
 use style_traits::{ParseError, StyleParseErrorKind, ToCss};
 
-/// Specified and computed `quote` property
+/// Specified and computed `quote` property.
+///
+/// FIXME(emilio): It's a shame that this allocates all the time it's computed,
+/// probably should just be refcounted.
 #[derive(Clone, Debug, MallocSizeOf, PartialEq, ToComputedValue)]
-pub struct Quotes(pub Vec<(String, String)>);
+pub struct Quotes(pub Box<[(Box<str>, Box<str>)]>);
 
 impl ToCss for Quotes {
     fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
-        if self.0.is_empty() {
-            return dest.write_str("none")
+        let mut iter = self.0.iter();
+
+        match iter.next() {
+            Some(&(ref l, ref r)) => {
+                l.to_css(dest)?;
+                dest.write_char(' ')?;
+                r.to_css(dest)?;
+            }
+            None => return dest.write_str("none"),
         }
 
-        let mut first = true;
-        for pair in &self.0 {
-            if !first {
-                dest.write_str(" ")?;
-            }
-            first = false;
-            serialize_string(&*pair.0, dest)?;
-            dest.write_str(" ")?;
-            serialize_string(&*pair.1, dest)?;
+        for &(ref l, ref r) in iter {
+            dest.write_char(' ')?;
+            l.to_css(dest)?;
+            dest.write_char(' ')?;
+            r.to_css(dest)?;
         }
+
         Ok(())
     }
 }
@@ -36,27 +43,27 @@ impl ToCss for Quotes {
 impl Parse for Quotes {
     fn parse<'i, 't>(_: &ParserContext, input: &mut Parser<'i, 't>) -> Result<Quotes, ParseError<'i>> {
         if input.try(|input| input.expect_ident_matching("none")).is_ok() {
-            return Ok(Quotes(Vec::new()))
+            return Ok(Quotes(Vec::new().into_boxed_slice()))
         }
 
         let mut quotes = Vec::new();
         loop {
             let location = input.current_source_location();
             let first = match input.next() {
-                Ok(&Token::QuotedString(ref value)) => value.as_ref().to_owned(),
+                Ok(&Token::QuotedString(ref value)) => {
+                    value.as_ref().to_owned().into_boxed_str()
+                },
                 Ok(t) => return Err(location.new_unexpected_token_error(t.clone())),
                 Err(_) => break,
             };
-            let location = input.current_source_location();
-            let second = match input.next() {
-                Ok(&Token::QuotedString(ref value)) => value.as_ref().to_owned(),
-                Ok(t) => return Err(location.new_unexpected_token_error(t.clone())),
-                Err(e) => return Err(e.into()),
-            };
+
+            let second =
+                input.expect_string()?.as_ref().to_owned().into_boxed_str();
             quotes.push((first, second))
         }
+
         if !quotes.is_empty() {
-            Ok(Quotes(quotes))
+            Ok(Quotes(quotes.into_boxed_slice()))
         } else {
             Err(input.new_custom_error(StyleParseErrorKind::UnspecifiedError))
         }