Auto merge of #10626 - sliz1:10576, r=KiChjang

Use the document base url when resolving iframe URLs

Fixes #10576.

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components/script/dom/htmliframeelement.rs

@@ -82,8 +82,7 @@ impl HTMLIFrameElement {
             if url.is_empty() {
                 None
             } else {
-                let window = window_from_node(self);
-                window.get_url().join(&url).ok()
+                document_from_node(self).base_url().join(&url).ok()
             }
         })
     }