--- a/layout/style/ServoBindings.cpp
+++ b/layout/style/ServoBindings.cpp
@@ -572,17 +572,16 @@ Gecko_StyleAnimationsEquals(RawGeckoStyl
 {
   return *aA == *aB;
 }
 
 void
 Gecko_UpdateAnimations(RawGeckoElementBorrowed aElement,
                        ServoComputedValuesBorrowedOrNull aOldComputedValues,
                        ServoComputedValuesBorrowedOrNull aComputedValues,
-                       ServoComputedValuesBorrowedOrNull aParentComputedValues,
                        UpdateAnimationsTasks aTasks)
 {
   MOZ_ASSERT(NS_IsMainThread());
   MOZ_ASSERT(aElement);
 
   nsPresContext* presContext = nsContentUtils::GetContextForContent(aElement);
   if (!presContext) {
     return;

--- a/layout/style/ServoBindings.h
+++ b/layout/style/ServoBindings.h
@@ -217,17 +217,16 @@ Gecko_GetAnimationRule(RawGeckoElementBo
                        RawServoAnimationValueMapBorrowedMut aAnimationValues);
 RawServoDeclarationBlockStrongBorrowedOrNull
 Gecko_GetSMILOverrideDeclarationBlock(RawGeckoElementBorrowed element);
 bool Gecko_StyleAnimationsEquals(RawGeckoStyleAnimationListBorrowed,
                                  RawGeckoStyleAnimationListBorrowed);
 void Gecko_UpdateAnimations(RawGeckoElementBorrowed aElementOrPseudo,
                             ServoComputedValuesBorrowedOrNull aOldComputedValues,
                             ServoComputedValuesBorrowedOrNull aComputedValues,
-                            ServoComputedValuesBorrowedOrNull aParentComputedValues,
                             mozilla::UpdateAnimationsTasks aTasks);
 bool Gecko_ElementHasAnimations(RawGeckoElementBorrowed aElementOrPseudo);
 bool Gecko_ElementHasCSSAnimations(RawGeckoElementBorrowed aElementOrPseudo);
 bool Gecko_ElementHasCSSTransitions(RawGeckoElementBorrowed aElementOrPseudo);
 size_t Gecko_ElementTransitions_Length(RawGeckoElementBorrowed aElementOrPseudo);
 nsCSSPropertyID Gecko_ElementTransitions_PropertyAt(
   RawGeckoElementBorrowed aElementOrPseudo,
   size_t aIndex);