Use feature try_borrow instead of borrow_state in script

components/script/lib.rs

@@ -3,7 +3,6 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #![feature(as_unsafe_cell)]
-#![feature(borrow_state)]
 #![feature(box_syntax)]
 #![feature(conservative_impl_trait)]
 #![feature(const_fn)]
@@ -19,6 +18,7 @@
 #![feature(slice_patterns)]
 #![feature(stmt_expr_attributes)]
 #![feature(question_mark)]
+#![feature(try_borrow)]
 #![feature(try_from)]
 
 #![deny(unsafe_code)]