--- a/servo/components/style/traversal.rs
+++ b/servo/components/style/traversal.rs
@@ -42,17 +42,17 @@ bitflags! {
         /// @keyframes rules may have changed
         const FOR_CSS_RULE_CHANGES = 0x08,
     }
 }
 
 impl TraversalFlags {
     /// Returns true if the traversal is for animation-only restyles.
     pub fn for_animation_only(&self) -> bool {
-        self.contains(ANIMATION_ONLY)
+        self.intersects(ANIMATION_ONLY)
     }
 
     /// Returns true if the traversal is for unstyled children.
     pub fn for_unstyled_children_only(&self) -> bool {
         self.contains(UNSTYLED_CHILDREN_ONLY)
     }
 
     /// Returns true if the traversal is for a frame reconstruction.