Oilpan: Move the EventListener hierarchy to Oilpan's heap

Source/modules/webmidi/MIDIInput.cpp

Index: Source/modules/webmidi/MIDIInput.cpp
diff --git a/Source/modules/webmidi/MIDIInput.cpp b/Source/modules/webmidi/MIDIInput.cpp
index 4de9cc88b1130cd8e36676ae2063c42b418dafc2..e006b9ceb4d14567167c6a4607dae3917a431507 100644
--- a/Source/modules/webmidi/MIDIInput.cpp
+++ b/Source/modules/webmidi/MIDIInput.cpp
@@ -57,7 +57,7 @@ EventListener* MIDIInput::onmidimessage()
     return getAttributeEventListener(EventTypeNames::midimessage);
 }
 
-void MIDIInput::setOnmidimessage(PassRefPtr<EventListener> listener)
+void MIDIInput::setOnmidimessage(PassRefPtrWillBeRawPtr<EventListener> listener)
 {
     // Implicit open. It does nothing if the port is already opened.
     // See http://www.w3.org/TR/webmidi/#widl-MIDIPort-open-Promise-MIDIPort
@@ -66,7 +66,7 @@ void MIDIInput::setOnmidimessage(PassRefPtr<EventListener> listener)
     setAttributeEventListener(EventTypeNames::midimessage, listener);
 }
 
-bool MIDIInput::addEventListener(const AtomicString& eventType, PassRefPtr<EventListener> listener, bool useCapture)
+bool MIDIInput::addEventListener(const AtomicString& eventType, PassRefPtrWillBeRawPtr<EventListener> listener, bool useCapture)
 {
     if (eventType == EventTypeNames::midimessage) {
         // Implicit open. See setOnmidimessage().