Add methods to move ByteStrings underlying bytes

Add methods to move the underlying Vec<u8> for ByteString.

tests/unit/script/dom/bindings.rs

@@ -0,0 +1,17 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+use script::dom::bindings::str::ByteString;
+
+#[test]
+fn test_byte_string_move() {
+    let mut byte_str = ByteString::new(vec![0x73, 0x65, 0x72, 0x76, 0x6f]);
+    let mut byte_vec = byte_str.bytes();
+
+    assert_eq!(byte_vec, "servo".as_bytes());
+    assert_eq!(*byte_str, []);
+
+    byte_vec = byte_str.into();
+    assert_eq!(byte_vec, Vec::new());
+}

tests/unit/script/lib.rs

@@ -9,5 +9,6 @@ extern crate util;
 #[cfg(all(test, target_pointer_width = "64"))] mod size_of;
 #[cfg(test)] mod textinput;
 #[cfg(test)] mod dom {
+    mod bindings;
     mod blob;
 }