--- a/servo/ports/geckolib/glue.rs
+++ b/servo/ports/geckolib/glue.rs
@@ -2101,20 +2101,19 @@ pub extern "C" fn Servo_StyleSet_FillKey
     };
 
     let style = ComputedValues::as_arc(&style);
     let global_style_data = &*GLOBAL_STYLE_DATA;
     let guard = global_style_data.shared_lock.read();
 
     for step in &animation.steps {
         // Override timing_function if the keyframe has animation-timing-function.
-        let timing_function = if let Some(val) = step.get_animation_timing_function(&guard) {
-            val.into()
-        } else {
-            *timing_function
+        let timing_function = match step.get_animation_timing_function(&guard) {
+            Some(val) => val.into(),
+            None => *timing_function,
         };
 
         let keyframe = unsafe {
             Gecko_AnimationAppendKeyframe(keyframes,
                                           step.start_percentage.0 as f32,
                                           &timing_function)
         };