--- a/gfx/layers/composite/ContainerLayerComposite.cpp
+++ b/gfx/layers/composite/ContainerLayerComposite.cpp
@@ -161,22 +161,22 @@ static gfx::IntRect ContainerVisibleRect
   gfx::IntRect surfaceRect = aContainer->GetLocalVisibleRegion().ToUnknownRegion().GetBounds();
   return surfaceRect;
 }
 
 
 /* all of the per-layer prepared data we need to maintain */
 struct PreparedLayer
 {
-  PreparedLayer(LayerComposite *aLayer,
+  PreparedLayer(Layer *aLayer,
                 RenderTargetIntRect aClipRect,
                 Maybe<gfx::Polygon>&& aGeometry)
   : mLayer(aLayer), mClipRect(aClipRect), mGeometry(Move(aGeometry)) {}
 
-  LayerComposite* mLayer;
+  RefPtr<Layer> mLayer;
   RenderTargetIntRect mClipRect;
   Maybe<Polygon> mGeometry;
 };
 
 /* all of the prepared data that we need in RenderLayer() */
 struct PreparedData
 {
   RefPtr<CompositingRenderTarget> mTmpTarget;
@@ -230,17 +230,18 @@ ContainerPrepare(ContainerT* aContainer,
         CULLING_LOG("Sublayer %p has an empty world clip rect\n", layerToRender->GetLayer());
         continue;
       }
     }
 
     CULLING_LOG("Preparing sublayer %p\n", layerToRender->GetLayer());
 
     layerToRender->Prepare(clipRect);
-    aContainer->mPrepared->mLayers.AppendElement(PreparedLayer(layerToRender, clipRect,
+    aContainer->mPrepared->mLayers.AppendElement(PreparedLayer(layerToRender->GetLayer(),
+                                                               clipRect,
                                                                Move(layer.geometry)));
   }
 
   CULLING_LOG("Preparing container layer %p\n", aContainer->GetLayer());
 
   /**
    * Setup our temporary surface for rendering the contents of this container.
    */
@@ -408,17 +409,17 @@ RenderLayers(ContainerT* aContainer, Lay
              const Maybe<gfx::Polygon>& aGeometry)
 {
   Compositor* compositor = aManager->GetCompositor();
 
   for (size_t i = 0u; i < aContainer->mPrepared->mLayers.Length(); i++) {
     PreparedLayer& preparedData = aContainer->mPrepared->mLayers[i];
 
     const gfx::IntRect clipRect = preparedData.mClipRect.ToUnknownRect();
-    LayerComposite* layerToRender = preparedData.mLayer;
+    LayerComposite* layerToRender = static_cast<LayerComposite*>(preparedData.mLayer->ImplData());
     const Maybe<gfx::Polygon>& childGeometry = preparedData.mGeometry;
 
     Layer* layer = layerToRender->GetLayer();
 
     if (layerToRender->HasStaleCompositor()) {
       continue;
     }