Oilpan: make Supplementable tracing more regular.

Source/core/html/HTMLMediaElement.cpp

Index: Source/core/html/HTMLMediaElement.cpp
diff --git a/Source/core/html/HTMLMediaElement.cpp b/Source/core/html/HTMLMediaElement.cpp
index b0c66c595aee4c68773af6c5ec4e52d032aa7635..284cd74cd83a1abeb9a21c0054d4d5dea787ca9c 100644
--- a/Source/core/html/HTMLMediaElement.cpp
+++ b/Source/core/html/HTMLMediaElement.cpp
@@ -3999,6 +3999,7 @@ void HTMLMediaElement::defaultEventHandler(Event* event)
 
 void HTMLMediaElement::trace(Visitor* visitor)
 {
+#if ENABLE(OILPAN)
     visitor->trace(m_playedTimeRanges);
     visitor->trace(m_asyncEventQueue);
     visitor->trace(m_error);
@@ -4013,7 +4014,8 @@ void HTMLMediaElement::trace(Visitor* visitor)
 #if ENABLE(WEB_AUDIO)
     visitor->registerWeakMembers<HTMLMediaElement, &HTMLMediaElement::clearWeakMembers>(this);
 #endif
-    WillBeHeapSupplementable<HTMLMediaElement>::trace(visitor);
+    HeapSupplementable<HTMLMediaElement>::trace(visitor);
+#endif
     HTMLElement::trace(visitor);
 }