Oilpan: Move LifecycleNotifier's hierarchy to Oilpan's heap

Source/modules/webmidi/MIDIAccessInitializer.cpp

Index: Source/modules/webmidi/MIDIAccessInitializer.cpp
diff --git a/Source/modules/webmidi/MIDIAccessInitializer.cpp b/Source/modules/webmidi/MIDIAccessInitializer.cpp
index 8890a80a6985cf97f4d51b3f360ce104c057cbdb..fc2f3d5e21fc9a79372ef5799ec899e37d1fe465 100644
--- a/Source/modules/webmidi/MIDIAccessInitializer.cpp
+++ b/Source/modules/webmidi/MIDIAccessInitializer.cpp
@@ -23,17 +23,6 @@ MIDIAccessInitializer::MIDIAccessInitializer(ScriptState* scriptState, const MID
     , m_hasBeenDisposed(false)
     , m_sysexPermissionResolved(false)
 {
-#if ENABLE(OILPAN)
-    // A prefinalizer has already been registered (as a LifecycleObserver);
-    // remove it and register a combined one, as the infrastructure doesn't
-    // support multiple prefinalizers for an object.
-    //
-    // FIXME: Oilpan: remove LifecycleObserver's need for a prefinalizer,
-    // and as a consequence, this unregistration step. If the former is independently
-    // removed, the unregisterPreFinalizer() call will assert.
-    ThreadState::current()->unregisterPreFinalizer(*static_cast<LifecycleObserver*>(this));
-    ThreadState::current()->registerPreFinalizer(*this);
-#endif
     if (options.hasSysex())
         m_requestSysex = options.sysex();
 }
@@ -67,11 +56,6 @@ void MIDIAccessInitializer::dispose()
     }
 
     m_hasBeenDisposed = true;
-
-#if ENABLE(OILPAN)
-    // Delegate to LifecycleObserver's prefinalizer.
-    LifecycleObserver::dispose();
-#endif
 }
 
 ScriptPromise MIDIAccessInitializer::start()