Do not zero-initialize RawPtr.

Source/core/page/EventHandler.cpp

Index: Source/core/page/EventHandler.cpp
diff --git a/Source/core/page/EventHandler.cpp b/Source/core/page/EventHandler.cpp
index e0301a0034d9d5e7edd6564342e4facd19597c63..cdfab871e2c2f9096743b6852fa73d86fa46be92 100644
--- a/Source/core/page/EventHandler.cpp
+++ b/Source/core/page/EventHandler.cpp
@@ -3591,8 +3591,10 @@ bool EventHandler::handleTouchEvent(const PlatformTouchEvent& event)
     // Array of touches per state, used to assemble the 'changedTouches' list in the JS event.
     typedef HashSet<RefPtr<EventTarget> > EventTargetSet;
     struct {
+        STACK_ALLOCATED();
+    public:
         // The touches corresponding to the particular change state this struct instance represents.
-        RefPtrWillBeRawPtr<TouchList> m_touches;
+        RefPtrWillBeMember<TouchList> m_touches;
         // Set of targets involved in m_touches.
         EventTargetSet m_targets;
     } changedTouches[PlatformTouchPoint::TouchStateEnd];