Oilpan: Remove a visitor parameter from isHeapObjectAlive

Source/modules/mediasource/MediaSource.cpp

Index: Source/modules/mediasource/MediaSource.cpp
diff --git a/Source/modules/mediasource/MediaSource.cpp b/Source/modules/mediasource/MediaSource.cpp
index 3cd3288b0b4b006f29a1aebe7bda79158ddfee71..65f966f47c065588e0fff33c30fa4c5a54ea70ff 100644
--- a/Source/modules/mediasource/MediaSource.cpp
+++ b/Source/modules/mediasource/MediaSource.cpp
@@ -269,7 +269,7 @@ void MediaSource::clearWeakMembers(Visitor* visitor)
     // Oilpan: If the MediaSource survived, but its attached media
     // element did not, signal the element that it can safely
     // notify its MediaSource during finalization by calling close().
-    if (m_attachedElement && !visitor->isHeapObjectAlive(m_attachedElement)) {
+    if (m_attachedElement && !Heap::isHeapObjectAlive(m_attachedElement)) {
         m_attachedElement->setCloseMediaSourceWhenFinalizing();
         m_attachedElement.clear();
     }