Auto merge of #14576 - canaltinova:keyframes-name, r=Manishearth,emilio

Implement CSSKeyframesRule.name

<!-- Please describe your changes on the following line: -->
Implementation of CSSKeyframesRule.name

---
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors

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- [X] There are tests for these changes

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components/script/dom/csskeyframesrule.rs

@@ -5,6 +5,7 @@
 use cssparser::Parser;
 use dom::bindings::codegen::Bindings::CSSKeyframesRuleBinding;
 use dom::bindings::codegen::Bindings::CSSKeyframesRuleBinding::CSSKeyframesRuleMethods;
+use dom::bindings::error::{Error, ErrorResult};
 use dom::bindings::inheritance::Castable;
 use dom::bindings::js::{MutNullableJS, Root};
 use dom::bindings::reflector::{DomObject, reflect_dom_object};
@@ -15,6 +16,7 @@ use dom::cssrulelist::{CSSRuleList, RulesSource};
 use dom::cssstylesheet::CSSStyleSheet;
 use dom::window::Window;
 use parking_lot::RwLock;
+use servo_atoms::Atom;
 use std::sync::Arc;
 use style::keyframes::{Keyframe, KeyframeSelector};
 use style::parser::ParserContextExtraData;
@@ -101,6 +103,27 @@ impl CSSKeyframesRuleMethods for CSSKeyframesRule {
             self.rulelist().item(idx as u32)
         }).and_then(Root::downcast)
     }
+
+    // https://drafts.csswg.org/css-animations/#dom-csskeyframesrule-name
+    fn Name(&self) -> DOMString {
+        DOMString::from(&*self.keyframesrule.read().name)
+    }
+
+    // https://drafts.csswg.org/css-animations/#dom-csskeyframesrule-name
+    fn SetName(&self, value: DOMString) -> ErrorResult {
+        // https://github.com/w3c/csswg-drafts/issues/801
+        // Setting this property to a CSS-wide keyword or `none` will
+        // throw a Syntax Error.
+        match_ignore_ascii_case! { value,
+            "initial" => return Err(Error::Syntax),
+            "inherit" => return Err(Error::Syntax),
+            "unset" => return Err(Error::Syntax),
+            "none" => return Err(Error::Syntax),
+            _ => ()
+        }
+        self.keyframesrule.write().name = Atom::from(value);
+        Ok(())
+    }
 }
 
 impl SpecificCSSRule for CSSKeyframesRule {

components/script/dom/webidls/CSSKeyframesRule.webidl

@@ -5,7 +5,8 @@
 // https://drafts.csswg.org/css-animations/#interface-csskeyframesrule
 [Exposed=Window]
 interface CSSKeyframesRule : CSSRule {
-  //          attribute DOMString   name;
+  [SetterThrows]
+           attribute DOMString   name;
   readonly attribute CSSRuleList cssRules;
 
   void            appendRule(DOMString rule);