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Source/bindings/core/v8/custom/V8InjectedScriptHostCustom.cpp

Index: Source/bindings/core/v8/custom/V8InjectedScriptHostCustom.cpp
diff --git a/Source/bindings/core/v8/custom/V8InjectedScriptHostCustom.cpp b/Source/bindings/core/v8/custom/V8InjectedScriptHostCustom.cpp
index 55476a0721e44ca95694cdcd3d5fd91d77135c14..82e644457352351d971970f175df7d4a2ad312ad 100644
--- a/Source/bindings/core/v8/custom/V8InjectedScriptHostCustom.cpp
+++ b/Source/bindings/core/v8/custom/V8InjectedScriptHostCustom.cpp
@@ -172,6 +172,10 @@ void V8InjectedScriptHost::subtypeMethodCustom(const v8::FunctionCallbackInfo<v8
         v8SetReturnValue(info, v8AtomicString(isolate, "set"));
         return;
     }
+    if (value->IsMapIterator() || value->IsSetIterator()) {
+        v8SetReturnValue(info, v8AtomicString(isolate, "iterator"));
+        return;
+    }
     if (V8Node::hasInstance(value, isolate)) {
         v8SetReturnValue(info, v8AtomicString(isolate, "node"));
         return;