--- a/layout/style/ServoBindings.cpp
+++ b/layout/style/ServoBindings.cpp
@@ -1712,16 +1712,22 @@ Gecko_CSSValue_SetString(nsCSSValueBorro
 void
 Gecko_CSSValue_SetStringFromAtom(nsCSSValueBorrowedMut aCSSValue,
                                  nsIAtom* aAtom, nsCSSUnit aUnit)
 {
   aCSSValue->SetStringValue(nsDependentAtomString(aAtom), aUnit);
 }
 
 void
+Gecko_CSSValue_SetAtomIdent(nsCSSValueBorrowedMut aCSSValue, nsIAtom* aAtom)
+{
+  aCSSValue->SetAtomIdentValue(already_AddRefed<nsIAtom>(aAtom));
+}
+
+void
 Gecko_CSSValue_SetArray(nsCSSValueBorrowedMut aCSSValue, int32_t aLength)
 {
   MOZ_ASSERT(aCSSValue->GetUnit() == eCSSUnit_Null);
   RefPtr<nsCSSValue::Array> array
     = nsCSSValue::Array::Create(aLength);
   aCSSValue->SetArrayValue(array, eCSSUnit_Array);
 }
 

--- a/layout/style/ServoBindings.h
+++ b/layout/style/ServoBindings.h
@@ -415,16 +415,18 @@ void Gecko_CSSValue_SetNumber(nsCSSValue
 void Gecko_CSSValue_SetKeyword(nsCSSValueBorrowedMut css_value, nsCSSKeyword keyword);
 void Gecko_CSSValue_SetPercentage(nsCSSValueBorrowedMut css_value, float percent);
 void Gecko_CSSValue_SetCalc(nsCSSValueBorrowedMut css_value, nsStyleCoord::CalcValue calc);
 void Gecko_CSSValue_SetFunction(nsCSSValueBorrowedMut css_value, int32_t len);
 void Gecko_CSSValue_SetString(nsCSSValueBorrowedMut css_value,
                               const uint8_t* string, uint32_t len, nsCSSUnit unit);
 void Gecko_CSSValue_SetStringFromAtom(nsCSSValueBorrowedMut css_value,
                                       nsIAtom* atom, nsCSSUnit unit);
+// Take an addrefed nsIAtom and set it to the nsCSSValue
+void Gecko_CSSValue_SetAtomIdent(nsCSSValueBorrowedMut css_value, nsIAtom* atom);
 void Gecko_CSSValue_SetArray(nsCSSValueBorrowedMut css_value, int32_t len);
 void Gecko_CSSValue_SetURL(nsCSSValueBorrowedMut css_value, ServoBundledURI uri);
 void Gecko_CSSValue_SetInt(nsCSSValueBorrowedMut css_value, int32_t integer, nsCSSUnit unit);
 void Gecko_CSSValue_Drop(nsCSSValueBorrowedMut css_value);
 NS_DECL_THREADSAFE_FFI_REFCOUNTING(nsCSSValueSharedList, CSSValueSharedList);
 bool Gecko_PropertyId_IsPrefEnabled(nsCSSPropertyID id);
 
 void Gecko_nsStyleFont_SetLang(nsStyleFont* font, nsIAtom* atom);