Auto merge of #228 - servo:unicode-range-repr-c, r=SimonSapin

unicode_range: Make UnicodeRange repr(C).

I want to expose it to Gecko via cbindgen without copies to extinguish
nsCSSValue.

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Author: bors-servo

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "cssparser"
-version = "0.24.0"
+version = "0.24.1"
 authors = [ "Simon Sapin <simon.sapin@exyr.org>" ]
 
 description = "Rust implementation of CSS Syntax Level 3"

src/unicode_range.rs

@@ -13,6 +13,7 @@ use tokenizer::Token;
 ///
 /// Can not be empty. Can represent a single code point when start == end.
 #[derive(PartialEq, Eq, Clone, Hash)]
+#[repr(C)]
 pub struct UnicodeRange {
     /// Inclusive start of the range. In [0, end].
     pub start: u32,