Improve DEFINE_STATIC_LOCAL()'s handling of Blink GCed objects.

third_party/WebKit/Source/core/input/EventHandler.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2012 Digia Plc. and/or its subsidiary(-ies)
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
@@ skipping 283 matching lines @@
     visitor->trace(m_scrollGestureHandlingNode);
     visitor->trace(m_previousGestureScrolledNode);
     visitor->trace(m_lastDeferredTapElement);
     visitor->trace(m_selectionController);
     visitor->trace(m_pointerEventManager);
 #endif
 }
 
 DragState& EventHandler::dragState()
 {
-    DEFINE_STATIC_LOCAL(Persistent<DragState>, state, (new DragState()));
-    return *state;
+    DEFINE_STATIC_LOCAL(DragState, state, (new DragState));
+    return state;
 }
 
 void EventHandler::clear()
 {
     m_hoverTimer.stop();
     m_cursorUpdateTimer.stop();
     m_fakeMouseMoveEventTimer.stop();
     m_activeIntervalTimer.stop();
     m_resizeScrollableArea = nullptr;
     m_nodeUnderMouse = nullptr;
@@ skipping 3676 matching lines @@
 PlatformEvent::Modifiers EventHandler::accessKeyModifiers()
 {
 #if OS(MACOSX)
     return static_cast<PlatformEvent::Modifiers>(PlatformEvent::CtrlKey | PlatformEvent::AltKey);
 #else
     return PlatformEvent::AltKey;
 #endif
 }
 
 } // namespace blink