Move util::cache to style.

tests/unit/style/cache.rs

@@ -3,7 +3,7 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 use std::cell::Cell;
-use util::cache::LRUCache;
+use style::cache::LRUCache;
 
 #[test]
 fn test_lru_cache() {

tests/unit/style/lib.rs

@@ -18,6 +18,7 @@ extern crate url;
 extern crate util;
 
 mod attr;
+mod cache;
 mod logical_geometry;
 mod media_queries;
 mod properties;

tests/unit/util/lib.rs

@@ -6,7 +6,6 @@
 
 extern crate util;
 
-mod cache;
 mod opts;
 mod prefs;
 mod thread;