Replace RwLock<CssRules> with Locked<CssRules>

tests/unit/style/media_queries.rs

@@ -35,7 +35,7 @@ fn test_media_rule<F>(css: &str, callback: F)
         ParserContextExtraData::default());
     let mut rule_count = 0;
     let guard = stylesheet.shared_lock.read();
-    media_queries(&guard, &stylesheet.rules.read().0, &mut |mq| {
+    media_queries(&guard, &stylesheet.rules.read_with(&guard).0, &mut |mq| {
         rule_count += 1;
         callback(mq, css);
     });

tests/unit/style/rule_tree/bench.rs

@@ -49,7 +49,8 @@ fn parse_rules(css: &str) -> Vec<(StyleSource, CascadeLevel)> {
                                  None,
                                  &ErrorringErrorReporter,
                                  ParserContextExtraData {});
-    let rules = s.rules.read();
+    let guard = s.shared_lock.read();
+    let rules = s.rules.read_with(&guard);
     rules.0.iter().filter_map(|rule| {
         match *rule {
             CssRule::Style(ref style_rule) => Some(style_rule),

tests/unit/style/stylesheets.rs

@@ -263,7 +263,7 @@ fn test_parse_stylesheet() {
                 ]
             })))
 
-        ]),
+        ], &stylesheet.shared_lock),
     };
 
     assert_eq!(format!("{:#?}", stylesheet), format!("{:#?}", expected));