Auto merge of #17005 - emilio:backdrop-fixup, r=emilio

stylo: Fixup an embarrassing typo that has turned everything orange.

I messed up when turning the conditions the other way around in #16981.

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components/style/gecko/pseudo_element.rs

@@ -55,7 +55,7 @@ impl PseudoElement {
     /// This is not the common thing, but there are some pseudos (namely:
     /// ::backdrop), that shouldn't inherit from the parent element.
     pub fn inherits_from_default_values(&self) -> bool {
-        !matches!(*self, PseudoElement::Backdrop)
+        matches!(*self, PseudoElement::Backdrop)
     }
 
     /// Gets the canonical index of this eagerly-cascaded pseudo-element.