--- a/dom/animation/DocumentTimeline.cpp
+++ b/dom/animation/DocumentTimeline.cpp
@@ -88,17 +88,17 @@ DocumentTimeline::GetCurrentTimeStamp() 
   // Always return the same object to benefit from return-value optimization.
   TimeStamp result = !refreshTime.IsNull()
                      ? refreshTime
                      : mLastRefreshDriverTime;
 
   // If we don't have a refresh driver and we've never had one use the
   // timeline's zero time.
   if (result.IsNull()) {
-    RefPtr<nsDOMNavigationTiming> timing = mDocument->GetNavigationTiming();
+    nsDOMNavigationTiming* timing = mDocument->GetNavigationTiming();
     if (timing) {
       result = timing->GetNavigationStartTimeStamp();
       // Also, let this time represent the current refresh time. This way
       // we'll save it as the last refresh time and skip looking up
       // navigation timing each time.
       refreshTime = result;
     }
   }
@@ -113,17 +113,17 @@ DocumentTimeline::GetCurrentTimeStamp() 
 Nullable<TimeDuration>
 DocumentTimeline::ToTimelineTime(const TimeStamp& aTimeStamp) const
 {
   Nullable<TimeDuration> result; // Initializes to null
   if (aTimeStamp.IsNull()) {
     return result;
   }
 
-  RefPtr<nsDOMNavigationTiming> timing = mDocument->GetNavigationTiming();
+  nsDOMNavigationTiming* timing = mDocument->GetNavigationTiming();
   if (MOZ_UNLIKELY(!timing)) {
     return result;
   }
 
   result.SetValue(aTimeStamp
                   - timing->GetNavigationStartTimeStamp()
                   - mOriginTime);
   return result;