Add [WillBeGarbageCollected] to Event.idl

Source/core/xml/XMLHttpRequestProgressEvent.h

Index: Source/core/xml/XMLHttpRequestProgressEvent.h
diff --git a/Source/core/xml/XMLHttpRequestProgressEvent.h b/Source/core/xml/XMLHttpRequestProgressEvent.h
index 5e7aa4608ca6df92ce794c732bf0d2468d7eb171..5a0f85d4a7e536aeee205b10f912973692a5b2b0 100644
--- a/Source/core/xml/XMLHttpRequestProgressEvent.h
+++ b/Source/core/xml/XMLHttpRequestProgressEvent.h
@@ -34,13 +34,13 @@ namespace WebCore {
 
 class XMLHttpRequestProgressEvent FINAL : public ProgressEvent {
 public:
-    static PassRefPtr<XMLHttpRequestProgressEvent> create()
+    static PassRefPtrWillBeRawPtr<XMLHttpRequestProgressEvent> create()
     {
-        return adoptRef(new XMLHttpRequestProgressEvent);
+        return adoptRefCountedWillBeRefCountedGarbageCollected(new XMLHttpRequestProgressEvent);
     }
-    static PassRefPtr<XMLHttpRequestProgressEvent> create(const AtomicString& type, bool lengthComputable = false, unsigned long long loaded = 0, unsigned long long total = 0)
+    static PassRefPtrWillBeRawPtr<XMLHttpRequestProgressEvent> create(const AtomicString& type, bool lengthComputable = false, unsigned long long loaded = 0, unsigned long long total = 0)
     {
-        return adoptRef(new XMLHttpRequestProgressEvent(type, lengthComputable, loaded, total));
+        return adoptRefCountedWillBeRefCountedGarbageCollected(new XMLHttpRequestProgressEvent(type, lengthComputable, loaded, total));
     }
 
     // Those 2 synonyms are included for compatibility with Firefox.