Make Event RefCountedGarbageCollected and implement trace() methods to the Event hierarcy

Source/core/speech/SpeechInputEvent.cpp

Index: Source/core/speech/SpeechInputEvent.cpp
diff --git a/Source/core/speech/SpeechInputEvent.cpp b/Source/core/speech/SpeechInputEvent.cpp
index f0222e9bb7763ab5c7d990f945537fa23981f898..8d88763215696358abe5faa67378c62e1f4da3da 100644
--- a/Source/core/speech/SpeechInputEvent.cpp
+++ b/Source/core/speech/SpeechInputEvent.cpp
@@ -69,6 +69,12 @@ const AtomicString& SpeechInputEvent::interfaceName() const
     return EventNames::SpeechInputEvent;
 }
 
+void SpeechInputEvent::trace(Visitor* visitor)
+{
+    visitor->trace(m_results);
+    Event::trace(visitor);
+}
+
 } // namespace WebCore
 
 #endif // ENABLE(INPUT_SPEECH)