Auto merge of #11589 - GuillaumeGomez:contains, r=nox

Make DOMTokenList.contains not throw anymore

Fixes #11579.

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2 files changed, 9 insertions, 10 deletions

diff --git a/components/script/dom/domtokenlist.rs b/components/script/dom/domtokenlist.rs
index dabf3bf4cb9..1fb53e6ce06 100644
--- a/components/script/dom/domtokenlist.rs
+++ b/components/script/dom/domtokenlist.rs
@@ -70,15 +70,14 @@ impl DOMTokenListMethods for DOMTokenList {
     }
 
     // https://dom.spec.whatwg.org/#dom-domtokenlist-contains
-    fn Contains(&self, token: DOMString) -> Fallible<bool> {
-        self.check_token_exceptions(&token).map(|token| {
-            self.attribute().map_or(false, |attr| {
-                let attr = attr.r();
-                attr.value()
-                    .as_tokens()
-                    .iter()
-                    .any(|atom: &Atom| *atom == token)
-            })
+    fn Contains(&self, token: DOMString) -> bool {
+        let token = Atom::from(token);
+        self.attribute().map_or(false, |attr| {
+            let attr = attr.r();
+            attr.value()
+                .as_tokens()
+                .iter()
+                .any(|atom: &Atom| *atom == token)
         })
     }
 
diff --git a/components/script/dom/webidls/DOMTokenList.webidl b/components/script/dom/webidls/DOMTokenList.webidl
index 1b50c34c918..2b7da5dea74 100644
--- a/components/script/dom/webidls/DOMTokenList.webidl
+++ b/components/script/dom/webidls/DOMTokenList.webidl
@@ -9,7 +9,7 @@ interface DOMTokenList {
   [Pure]
   getter DOMString? item(unsigned long index);
 
-  [Pure, Throws]
+  [Pure]
   boolean contains(DOMString token);
   [Throws]
   void add(DOMString... tokens);