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/script/dom/htmllinkelement.rs

@@ -370,12 +370,10 @@ impl FetchResponseListener for StylesheetContext {
 
             let win = window_from_node(&*elem);
 
-            let mut sheet = Stylesheet::from_bytes(&data, final_url, protocol_encoding_label,
-                                                   Some(environment_encoding), Origin::Author,
-                                                   win.css_error_reporter(),
-                                                   ParserContextExtraData::default());
-            sheet.set_media(self.media.take().unwrap());
-            let sheet = Arc::new(sheet);
+            let sheet = Arc::new(Stylesheet::from_bytes(
+                &data, final_url, protocol_encoding_label, Some(environment_encoding),
+                Origin::Author, self.media.take().unwrap(), win.css_error_reporter(),
+                ParserContextExtraData::default()));
 
             let win = window_from_node(&*elem);
             win.layout_chan().send(Msg::AddStylesheet(sheet.clone())).unwrap();

components/script/dom/htmlmetaelement.rs

@@ -21,6 +21,7 @@ use html5ever_atoms::LocalName;
 use parking_lot::RwLock;
 use std::ascii::AsciiExt;
 use std::sync::Arc;
+use std::sync::atomic::AtomicBool;
 use style::attr::AttrValue;
 use style::str::HTML_SPACE_CHARACTERS;
 use style::stylesheets::{Stylesheet, CssRule, Origin};
@@ -101,7 +102,7 @@ impl HTMLMetaElement {
                         media: Default::default(),
                         // Viewport constraints are always recomputed on resize; they don't need to
                         // force all styles to be recomputed.
-                        dirty_on_viewport_size_change: false,
+                        dirty_on_viewport_size_change: AtomicBool::new(false),
                     }));
                     let doc = document_from_node(self);
                     doc.invalidate_stylesheets();

components/script/dom/htmlstyleelement.rs

@@ -65,10 +65,9 @@ impl HTMLStyleElement {
         };
 
         let data = node.GetTextContent().expect("Element.textContent must be a string");
-        let mut sheet = Stylesheet::from_str(&data, url, Origin::Author, win.css_error_reporter(),
-                                             ParserContextExtraData::default());
-        let mut css_parser = CssParser::new(&mq_str);
-        sheet.set_media(parse_media_query_list(&mut css_parser));
+        let mq = parse_media_query_list(&mut CssParser::new(&mq_str));
+        let sheet = Stylesheet::from_str(&data, url, Origin::Author, mq, win.css_error_reporter(),
+                                         ParserContextExtraData::default());
         let sheet = Arc::new(sheet);
 
         win.layout_chan().send(Msg::AddStylesheet(sheet.clone())).unwrap();