--- a/gfx/layers/ipc/CompositorBridgeParent.cpp
+++ b/gfx/layers/ipc/CompositorBridgeParent.cpp
@@ -1394,19 +1394,20 @@ CompositorBridgeParent::SetTestAsyncZoom
     mApzUpdater->SetTestAsyncZoom(aLayersId, aScrollId, aZoom);
   }
 }
 
 void
 CompositorBridgeParent::FlushApzRepaints(const LayersId& aLayersId)
 {
   MOZ_ASSERT(mApzcTreeManager);
+  MOZ_ASSERT(mApzUpdater);
   MOZ_ASSERT(aLayersId.IsValid());
   RefPtr<CompositorBridgeParent> self = this;
-  APZThreadUtils::RunOnControllerThread(NS_NewRunnableFunction(
+  mApzUpdater->RunOnControllerThread(aLayersId, NS_NewRunnableFunction(
     "layers::CompositorBridgeParent::FlushApzRepaints",
     [=]() { self->mApzcTreeManager->FlushApzRepaints(aLayersId); }));
 }
 
 void
 CompositorBridgeParent::GetAPZTestData(const LayersId& aLayersId,
                                        APZTestData* aOutData)
 {
@@ -1416,32 +1417,32 @@ CompositorBridgeParent::GetAPZTestData(c
   }
 }
 
 void
 CompositorBridgeParent::SetConfirmedTargetAPZC(const LayersId& aLayersId,
                                                const uint64_t& aInputBlockId,
                                                const nsTArray<ScrollableLayerGuid>& aTargets)
 {
-  if (!mApzcTreeManager) {
+  if (!mApzcTreeManager || !mApzUpdater) {
     return;
   }
   // Need to specifically bind this since it's overloaded.
   void (APZCTreeManager::*setTargetApzcFunc)
         (uint64_t, const nsTArray<ScrollableLayerGuid>&) =
         &APZCTreeManager::SetTargetAPZC;
   RefPtr<Runnable> task =
     NewRunnableMethod<uint64_t,
                       StoreCopyPassByConstLRef<nsTArray<ScrollableLayerGuid>>>(
       "layers::CompositorBridgeParent::SetConfirmedTargetAPZC",
       mApzcTreeManager.get(),
       setTargetApzcFunc,
       aInputBlockId,
       aTargets);
-  APZThreadUtils::RunOnControllerThread(task.forget());
+  mApzUpdater->RunOnControllerThread(aLayersId, task.forget());
 }
 
 void
 CompositorBridgeParent::InitializeLayerManager(const nsTArray<LayersBackend>& aBackendHints)
 {
   NS_ASSERTION(!mLayerManager, "Already initialised mLayerManager");
   NS_ASSERTION(!mCompositor,   "Already initialised mCompositor");