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 878b6dfd55ebf4c36fac13d33590a0ceb8fe3fc5..30fbaac6f25f91345355c7fa6cc3b3b59cb077c6 100644
--- a/Source/core/xml/XMLHttpRequestProgressEvent.h
+++ b/Source/core/xml/XMLHttpRequestProgressEvent.h
@@ -33,13 +33,13 @@ namespace WebCore {
 
 class XMLHttpRequestProgressEvent FINAL : public ProgressEvent {
 public:
-    static PassRefPtr<XMLHttpRequestProgressEvent> create()
+    static PassRefPtrWillBeRawPtr<XMLHttpRequestProgressEvent> create()
     {
-        return adoptRef(new XMLHttpRequestProgressEvent);
+        return adoptRefWillBeRefCountedGarbageCollected(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 adoptRefWillBeRefCountedGarbageCollected(new XMLHttpRequestProgressEvent(type, lengthComputable, loaded, total));
     }
 
     // Those 2 synonyms are included for compatibility with Firefox.