Auto merge of #14121 - upsuper:medialist, r=Wafflespeanut

Rename media_queries::MediaQueryList to MediaList

<!-- Please describe your changes on the following line: -->
`MediaList` is the name of the interface for "collection of media queries" used in [CSSOM spec](https://drafts.csswg.org/cssom/#the-medialist-interface), `MediaQueryList` happens to mean something different in [CSSOM View spec](https://drafts.csswg.org/cssom-view/#the-mediaquerylist-interface), which also leads to naming conflict in dom code. So I think it's better renaming it to `MediaList`.

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- [x] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

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

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tests/unit/style/media_queries.rs

@@ -24,7 +24,7 @@ impl ParseErrorReporter for CSSErrorReporterTest {
      }
 }
 
-fn test_media_rule<F>(css: &str, callback: F) where F: Fn(&MediaQueryList, &str) {
+fn test_media_rule<F>(css: &str, callback: F) where F: Fn(&MediaList, &str) {
     let url = Url::parse("http://localhost").unwrap();
     let stylesheet = Stylesheet::from_str(css, url, Origin::Author, Box::new(CSSErrorReporterTest),
                                           ParserContextExtraData::default());
@@ -36,7 +36,7 @@ fn test_media_rule<F>(css: &str, callback: F) where F: Fn(&MediaQueryList, &str)
     assert!(rule_count > 0);
 }
 
-fn media_queries<F>(rules: &[CSSRule], f: &mut F) where F: FnMut(&MediaQueryList) {
+fn media_queries<F>(rules: &[CSSRule], f: &mut F) where F: FnMut(&MediaList) {
     for rule in rules {
         rule.with_nested_rules_and_mq(|rules, mq| {
             if let Some(mq) = mq {