diff --git a/gfx/layers/composite/LayerManagerComposite.cpp b/gfx/layers/composite/LayerManagerComposite.cpp
index ed03052b1f88..f531f7905c46 100644
--- a/gfx/layers/composite/LayerManagerComposite.cpp
+++ b/gfx/layers/composite/LayerManagerComposite.cpp
@@ -203,6 +203,7 @@ LayerManagerComposite::EndTransaction(DrawThebesLayerCallback aCallback,
                                       EndTransactionFlags aFlags)
 {
   NS_ASSERTION(mInTransaction, "Didn't call BeginTransaction?");
+  NS_ASSERTION(!aCallback && !aCallbackData, "Not expecting callbacks here");
   mInTransaction = false;
 
   if (!mIsCompositorReady) {
@@ -240,13 +241,7 @@ LayerManagerComposite::EndTransaction(DrawThebesLayerCallback aCallback,
     // so we don't need to pass any global transform here.
     mRoot->ComputeEffectiveTransforms(gfx3DMatrix());
 
-    mThebesLayerCallback = aCallback;
-    mThebesLayerCallbackData = aCallbackData;
-
     Render();
-
-    mThebesLayerCallback = nullptr;
-    mThebesLayerCallbackData = nullptr;
   }
 
   mCompositor->SetTargetContext(nullptr);
diff --git a/gfx/layers/composite/LayerManagerComposite.h b/gfx/layers/composite/LayerManagerComposite.h
index c9c6226b8182..5bf369302cd6 100644
--- a/gfx/layers/composite/LayerManagerComposite.h
+++ b/gfx/layers/composite/LayerManagerComposite.h
@@ -153,12 +153,6 @@ public:
     CreateOptimalMaskSurface(const gfxIntSize &aSize) MOZ_OVERRIDE;
 
 
-  DrawThebesLayerCallback GetThebesLayerCallback() const
-  { return mThebesLayerCallback; }
-
-  void* GetThebesLayerCallbackData() const
-  { return mThebesLayerCallbackData; }
-
   virtual const char* Name() const MOZ_OVERRIDE { return ""; }
 
   enum WorldTransforPolicy {
@@ -271,10 +265,6 @@ private:
   /** Our more efficient but less powerful alter ego, if one is available. */
   nsRefPtr<Composer2D> mComposer2D;
 
-  /* Thebes layer callbacks; valid at the end of a transaciton,
-   * while rendering */
-  DrawThebesLayerCallback mThebesLayerCallback;
-  void *mThebesLayerCallbackData;
   gfxMatrix mWorldMatrix;
 
   bool mInTransaction;