Auto merge of #7452 - nox:cleanup-attributes, r=nox

Introduce VirtualMethods::attribute_mutated()



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components/script/dom/htmlformelement.rs

@@ -316,7 +316,7 @@ impl HTMLFormElement {
                         _ => Some(FormDatum {
                             ty: ty,
                             name: name,
-                            value: input.Value()
+                            value: value
                         })
                     }
                 }