Auto merge of #14096 - fflorent:11485-make-dom-methods-taking-mut-JSContent-unsafe, r=nox

11485 make dom methods taking mut js content unsafe

This is a rebased version of PR #11595

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- [x] These changes fix #11485

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components/script/dom/node.rs

@@ -1394,7 +1394,7 @@ impl Node {
     pub fn reflect_node<N>(
             node: Box<N>,
             document: &Document,
-            wrap_fn: extern "Rust" fn(*mut JSContext, &GlobalScope, Box<N>) -> Root<N>)
+            wrap_fn: unsafe extern "Rust" fn(*mut JSContext, &GlobalScope, Box<N>) -> Root<N>)
             -> Root<N>
         where N: DerivedFrom<Node> + Reflectable
     {