1 files changed, 2 insertions, 2 deletions
diff --git a/chromium/third_party/blink/renderer/core/dom/mutation_observer.h b/chromium/third_party/blink/renderer/core/dom/mutation_observer.h
index 060b575349a..ae49ed221bd 100644
--- a/chromium/third_party/blink/renderer/core/dom/mutation_observer.h
+++ b/chromium/third_party/blink/renderer/core/dom/mutation_observer.h
@@ -86,7 +86,7 @@ class CORE_EXPORT MutationObserver final
     virtual ExecutionContext* GetExecutionContext() const = 0;
     virtual void Deliver(const MutationRecordVector& records,
                          MutationObserver&) = 0;
-    virtual void Trace(Visitor* visitor) {}
+    virtual void Trace(Visitor* visitor) const {}
     const char* NameInHeapSnapshot() const override {
       return "MutationObserver::Delegate";
     }
@@ -118,7 +118,7 @@ class CORE_EXPORT MutationObserver final
   void ContextLifecycleStateChanged(mojom::FrameLifecycleState) final;
   void ContextDestroyed() final {}
 
-  void Trace(Visitor*) override;
+  void Trace(Visitor*) const override;
 
  private:
   struct ObserverLessThan;