Auto merge of #9684 - danlrobertson:i9655, r=KiChjang

Add methods to move ByteStrings underlying bytes

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

I saw this as at least two methods. One to "move and replace with and empty Vec<u8> (`bytes`), and one to take ownership of the whole object (`own_bytes`). I typically also don't like adding methods with out unit tests. If you think they're unnecessary, just let me know.

As always, please let me know if you have any comments, critiques, or nits!

Fixes #9655

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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;
 }