Auto merge of #14232 - servo:moar-locks, r=upsuper

CSSOM: Make Stylesheet fields have their own synchronization

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r? @upsuper

---
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix bug 1314208.

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- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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components/layout_thread/lib.rs

@@ -1060,7 +1060,7 @@ impl LayoutThread {
                        .send(ConstellationMsg::ViewportConstrained(self.id, constraints))
                        .unwrap();
             }
-            if data.document_stylesheets.iter().any(|sheet| sheet.dirty_on_viewport_size_change) {
+            if data.document_stylesheets.iter().any(|sheet| sheet.dirty_on_viewport_size_change()) {
                 let mut iter = node.traverse_preorder();
 
                 let mut next = iter.next();
@@ -1533,6 +1533,7 @@ fn get_ua_stylesheets() -> Result<UserAgentStylesheets, &'static str> {
             None,
             None,
             Origin::UserAgent,
+            Default::default(),
             Box::new(StdoutErrorReporter),
             ParserContextExtraData::default()))
     }
@@ -1545,8 +1546,8 @@ fn get_ua_stylesheets() -> Result<UserAgentStylesheets, &'static str> {
     }
     for &(ref contents, ref url) in &opts::get().user_stylesheets {
         user_or_user_agent_stylesheets.push(Stylesheet::from_bytes(
-            &contents, url.clone(), None, None, Origin::User, Box::new(StdoutErrorReporter),
-            ParserContextExtraData::default()));
+            &contents, url.clone(), None, None, Origin::User, Default::default(),
+            Box::new(StdoutErrorReporter), ParserContextExtraData::default()));
     }
 
     let quirks_mode_stylesheet = try!(parse_ua_stylesheet("quirks-mode.css"));