[oilpan] The Node hierarchy should have correct accept method chains

Source/core/html/shadow/PickerIndicatorElement.cpp

Index: Source/core/html/shadow/PickerIndicatorElement.cpp
diff --git a/Source/core/html/shadow/PickerIndicatorElement.cpp b/Source/core/html/shadow/PickerIndicatorElement.cpp
index b5f027da8dce0bb8b823a6c5b2aedd75e1af7673..2f2d3f829c80bc0e9cf1462710a5dc0dcd258dc6 100644
--- a/Source/core/html/shadow/PickerIndicatorElement.cpp
+++ b/Source/core/html/shadow/PickerIndicatorElement.cpp
@@ -132,6 +132,11 @@ void PickerIndicatorElement::detach()
     HTMLDivElement::detach();
 }
 
+void PickerIndicatorElement::acceptHeapVisitor(Visitor* visitor) const
+{
+    HTMLDivElement::acceptHeapVisitor(visitor);
+}
+
 }
 
 #endif