--- a/layout/style/ServoBindings.cpp
+++ b/layout/style/ServoBindings.cpp
@@ -327,30 +327,28 @@ Gecko_GetStyleContext(RawGeckoElementBor
 CSSPseudoElementType
 Gecko_GetImplementedPseudo(RawGeckoElementBorrowed aElement)
 {
   return aElement->GetPseudoElementType();
 }
 
 nsChangeHint
 Gecko_CalcStyleDifference(nsStyleContext* aOldStyleContext,
-                          ServoComputedValuesBorrowed aComputedValues)
+                          ServoComputedValuesBorrowed aComputedValues,
+                          bool* aAnyStyleChanged)
 {
   MOZ_ASSERT(aOldStyleContext);
   MOZ_ASSERT(aComputedValues);
 
-  // Eventually, we should compute things out of these flags like
-  // ElementRestyler::RestyleSelf does and pass the result to the caller to
-  // potentially halt traversal. See bug 1289868.
   uint32_t equalStructs, samePointerStructs;
   nsChangeHint result =
     aOldStyleContext->CalcStyleDifference(aComputedValues,
                                           &equalStructs,
                                           &samePointerStructs);
-
+  *aAnyStyleChanged = equalStructs != NS_STYLE_INHERIT_MASK;
   return result;
 }
 
 nsChangeHint
 Gecko_HintsHandledForDescendants(nsChangeHint aHint)
 {
   return aHint & ~NS_HintsNotHandledForDescendantsIn(aHint);
 }

--- a/layout/style/ServoBindings.h
+++ b/layout/style/ServoBindings.h
@@ -317,17 +317,18 @@ void Gecko_SetOwnerDocumentNeedsStyleFlu
 
 // Incremental restyle.
 // Also, we might want a ComputedValues to ComputedValues API for animations?
 // Not if we do them in Gecko...
 nsStyleContext* Gecko_GetStyleContext(RawGeckoElementBorrowed element,
                                       nsIAtom* aPseudoTagOrNull);
 mozilla::CSSPseudoElementType Gecko_GetImplementedPseudo(RawGeckoElementBorrowed element);
 nsChangeHint Gecko_CalcStyleDifference(nsStyleContext* oldstyle,
-                                       ServoComputedValuesBorrowed newstyle);
+                                       ServoComputedValuesBorrowed newstyle,
+                                       bool* any_style_changed);
 nsChangeHint Gecko_HintsHandledForDescendants(nsChangeHint aHint);
 
 // Get an element snapshot for a given element from the table.
 const ServoElementSnapshot*
 Gecko_GetElementSnapshot(const mozilla::ServoElementSnapshotTable* table,
                          RawGeckoElementBorrowed element);
 
 void Gecko_DropElementSnapshot(ServoElementSnapshotOwned snapshot);