Auto merge of #15931 - emilio:die-defaultvalues-die, r=mbrubeck

style: Kill SharedStyleContext::default_computed_values.

This is on top of https://github.com/servo/servo/pull/15928.

Now that cascade() gets a Device ref, we can use the default computed values
from there to avoid propagating that state all over the place.

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3 files changed, 8 insertions, 6 deletions

diff --git a/components/script/dom/css.rs b/components/script/dom/css.rs
index e24b3657775..92c15a10067 100644
--- a/components/script/dom/css.rs
+++ b/components/script/dom/css.rs
@@ -29,7 +29,7 @@ impl CSS {
     pub fn Supports(win: &Window, property: DOMString, value: DOMString) -> bool {
         let decl = Declaration { prop: property.into(), val: value.into() };
         let url = win.Document().url();
-        let context = ParserContext::new_for_cssom(&url);
+        let context = ParserContext::new_for_cssom(&url, win.css_error_reporter());
         decl.eval(&context)
     }
 
@@ -39,7 +39,7 @@ impl CSS {
         let cond = parse_condition_or_declaration(&mut input);
         if let Ok(cond) = cond {
             let url = win.Document().url();
-            let context = ParserContext::new_for_cssom(&url);
+            let context = ParserContext::new_for_cssom(&url, win.css_error_reporter());
             cond.eval(&context)
         } else {
             false
diff --git a/components/script/dom/csssupportsrule.rs b/components/script/dom/csssupportsrule.rs
index 7b1e77a6c8f..0cc113bef1c 100644
--- a/components/script/dom/csssupportsrule.rs
+++ b/components/script/dom/csssupportsrule.rs
@@ -56,8 +56,10 @@ impl CSSSupportsRule {
         let mut input = Parser::new(&text);
         let cond = SupportsCondition::parse(&mut input);
         if let Ok(cond) = cond {
-            let url = self.global().as_window().Document().url();
-            let context = ParserContext::new_for_cssom(&url);
+            let global = self.global();
+            let win = global.as_window();
+            let url = win.Document().url();
+            let context = ParserContext::new_for_cssom(&url, win.css_error_reporter());
             let enabled = cond.eval(&context);
             let mut rule = self.supportsrule.write();
             rule.condition = cond;
diff --git a/components/script/dom/window.rs b/components/script/dom/window.rs
index 64a303c9412..fcb7f85d4cf 100644
--- a/components/script/dom/window.rs
+++ b/components/script/dom/window.rs
@@ -331,8 +331,8 @@ impl Window {
          &self.bluetooth_extra_permission_data
     }
 
-    pub fn css_error_reporter(&self) -> Box<ParseErrorReporter + Send> {
-        self.error_reporter.clone()
+    pub fn css_error_reporter(&self) -> &ParseErrorReporter {
+        &self.error_reporter
     }
 
     /// Sets a new list of scroll offsets.