diff --git a/gfx/layers/ipc/CompositorBridgeParent.cpp b/gfx/layers/ipc/CompositorBridgeParent.cpp
index 06cdce6668f0..b5666d174547 100644
--- a/gfx/layers/ipc/CompositorBridgeParent.cpp
+++ b/gfx/layers/ipc/CompositorBridgeParent.cpp
@@ -1266,7 +1266,7 @@ CompositorBridgeParent::ForceComposite(LayerTransactionParent* aLayerTree)
 }
 
 bool
-CompositorBridgeParent::SetTestSampleTime(LayerTransactionParent* aLayerTree,
+CompositorBridgeParent::SetTestSampleTime(const uint64_t& aId,
                                           const TimeStamp& aTime)
 {
   if (aTime.IsNull()) {
@@ -1295,7 +1295,7 @@ CompositorBridgeParent::SetTestSampleTime(LayerTransactionParent* aLayerTree,
 }
 
 void
-CompositorBridgeParent::LeaveTestMode(LayerTransactionParent* aLayerTree)
+CompositorBridgeParent::LeaveTestMode(const uint64_t& aId)
 {
   mIsTesting = false;
 }
diff --git a/gfx/layers/ipc/CompositorBridgeParent.h b/gfx/layers/ipc/CompositorBridgeParent.h
index 415cac05c482..b639688e6194 100644
--- a/gfx/layers/ipc/CompositorBridgeParent.h
+++ b/gfx/layers/ipc/CompositorBridgeParent.h
@@ -106,9 +106,9 @@ public:
   virtual void NotifyClearCachedResources(LayerTransactionParent* aLayerTree) { }
 
   virtual void ForceComposite(LayerTransactionParent* aLayerTree) { }
-  virtual bool SetTestSampleTime(LayerTransactionParent* aLayerTree,
+  virtual bool SetTestSampleTime(const uint64_t& aId,
                                  const TimeStamp& aTime) { return true; }
-  virtual void LeaveTestMode(LayerTransactionParent* aLayerTree) { }
+  virtual void LeaveTestMode(const uint64_t& aId) { }
   virtual void ApplyAsyncProperties(LayerTransactionParent* aLayerTree) = 0;
   virtual CompositorAnimationStorage* GetAnimationStorage(const uint64_t& aId) { return nullptr; }
   virtual void FlushApzRepaints(const uint64_t& aLayersId) = 0;
@@ -230,9 +230,9 @@ public:
                                    const TransactionInfo& aInfo,
                                    bool aHitTestUpdate) override;
   virtual void ForceComposite(LayerTransactionParent* aLayerTree) override;
-  virtual bool SetTestSampleTime(LayerTransactionParent* aLayerTree,
+  virtual bool SetTestSampleTime(const uint64_t& aId,
                                  const TimeStamp& aTime) override;
-  virtual void LeaveTestMode(LayerTransactionParent* aLayerTree) override;
+  virtual void LeaveTestMode(const uint64_t& aId) override;
   virtual void ApplyAsyncProperties(LayerTransactionParent* aLayerTree)
                override;
   virtual CompositorAnimationStorage* GetAnimationStorage(const uint64_t& aId) override;
diff --git a/gfx/layers/ipc/CrossProcessCompositorBridgeParent.cpp b/gfx/layers/ipc/CrossProcessCompositorBridgeParent.cpp
index 1887fc2333fc..47d03471be2b 100644
--- a/gfx/layers/ipc/CrossProcessCompositorBridgeParent.cpp
+++ b/gfx/layers/ipc/CrossProcessCompositorBridgeParent.cpp
@@ -365,34 +365,32 @@ CrossProcessCompositorBridgeParent::NotifyClearCachedResources(LayerTransactionP
 }
 
 bool
-CrossProcessCompositorBridgeParent::SetTestSampleTime(
-  LayerTransactionParent* aLayerTree, const TimeStamp& aTime)
+CrossProcessCompositorBridgeParent::SetTestSampleTime(const uint64_t& aId,
+                                                      const TimeStamp& aTime)
 {
-  uint64_t id = aLayerTree->GetId();
-  MOZ_ASSERT(id != 0);
+  MOZ_ASSERT(aId != 0);
   const CompositorBridgeParent::LayerTreeState* state =
-    CompositorBridgeParent::GetIndirectShadowTree(id);
+    CompositorBridgeParent::GetIndirectShadowTree(aId);
   if (!state) {
     return false;
   }
 
   MOZ_ASSERT(state->mParent);
-  return state->mParent->SetTestSampleTime(aLayerTree, aTime);
+  return state->mParent->SetTestSampleTime(aId, aTime);
 }
 
 void
-CrossProcessCompositorBridgeParent::LeaveTestMode(LayerTransactionParent* aLayerTree)
+CrossProcessCompositorBridgeParent::LeaveTestMode(const uint64_t& aId)
 {
-  uint64_t id = aLayerTree->GetId();
-  MOZ_ASSERT(id != 0);
+  MOZ_ASSERT(aId != 0);
   const CompositorBridgeParent::LayerTreeState* state =
-    CompositorBridgeParent::GetIndirectShadowTree(id);
+    CompositorBridgeParent::GetIndirectShadowTree(aId);
   if (!state) {
     return;
   }
 
   MOZ_ASSERT(state->mParent);
-  state->mParent->LeaveTestMode(aLayerTree);
+  state->mParent->LeaveTestMode(aId);
 }
 
 void
diff --git a/gfx/layers/ipc/CrossProcessCompositorBridgeParent.h b/gfx/layers/ipc/CrossProcessCompositorBridgeParent.h
index 6da58d97e96b..fc835d26c04e 100644
--- a/gfx/layers/ipc/CrossProcessCompositorBridgeParent.h
+++ b/gfx/layers/ipc/CrossProcessCompositorBridgeParent.h
@@ -90,9 +90,9 @@ public:
                                    bool aHitTestUpdate) override;
   virtual void ForceComposite(LayerTransactionParent* aLayerTree) override;
   virtual void NotifyClearCachedResources(LayerTransactionParent* aLayerTree) override;
-  virtual bool SetTestSampleTime(LayerTransactionParent* aLayerTree,
+  virtual bool SetTestSampleTime(const uint64_t& aId,
                                  const TimeStamp& aTime) override;
-  virtual void LeaveTestMode(LayerTransactionParent* aLayerTree) override;
+  virtual void LeaveTestMode(const uint64_t& aId) override;
   virtual void ApplyAsyncProperties(LayerTransactionParent* aLayerTree)
                override;
   virtual CompositorAnimationStorage*
diff --git a/gfx/layers/ipc/LayerTransactionParent.cpp b/gfx/layers/ipc/LayerTransactionParent.cpp
index b6c0a9ab0dd7..49dc06c3f722 100644
--- a/gfx/layers/ipc/LayerTransactionParent.cpp
+++ b/gfx/layers/ipc/LayerTransactionParent.cpp
@@ -689,7 +689,7 @@ LayerTransactionParent::ShouldParentObserveEpoch()
 mozilla::ipc::IPCResult
 LayerTransactionParent::RecvSetTestSampleTime(const TimeStamp& aTime)
 {
-  if (!mCompositorBridge->SetTestSampleTime(this, aTime)) {
+  if (!mCompositorBridge->SetTestSampleTime(GetId(), aTime)) {
     return IPC_FAIL_NO_REASON(this);
   }
   return IPC_OK();
@@ -698,7 +698,7 @@ LayerTransactionParent::RecvSetTestSampleTime(const TimeStamp& aTime)
 mozilla::ipc::IPCResult
 LayerTransactionParent::RecvLeaveTestMode()
 {
-  mCompositorBridge->LeaveTestMode(this);
+  mCompositorBridge->LeaveTestMode(GetId());
   return IPC_OK();
 }