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

third_party/WebKit/Source/core/dom/ContextFeatures.h

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Neither the name of Google Inc. nor the names of its
@@ skipping 11 matching lines @@
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef ContextFeatures_h
 #define ContextFeatures_h
 
 #include "core/CoreExport.h"
 #include "core/page/Page.h"
+#include "platform/heap/Handle.h"
 
 namespace blink {
 
 class ContextFeaturesClient;
 class Document;
 class Page;
 
 class ContextFeatures final : public GarbageCollectedFinalized<ContextFeatures>, public Supplement<Page> {
     USING_GARBAGE_COLLECTED_MIXIN(ContextFeatures);
 public:
     enum FeatureType {
         PagePopup = 0,
         MutationEvents,
         FeatureTypeSize // Should be the last entry.
     };
 
     static const char* supplementName();
-    static ContextFeatures* defaultSwitch();
+    static ContextFeatures& defaultSwitch();
     static RawPtr<ContextFeatures> create(PassOwnPtr<ContextFeaturesClient>);
 
     static bool pagePopupEnabled(Document*);
     static bool mutationEventsEnabled(Document*);
 
     bool isEnabled(Document*, FeatureType, bool) const;
     void urlDidChange(Document*);
 
 private:
     explicit ContextFeatures(PassOwnPtr<ContextFeaturesClient> client)
@@ skipping 36 matching lines @@
     // See issue 294180
     //
     // if (m_client)
     //     return;
     // m_client->urlDidChange(document);
 }
 
 } // namespace blink
 
 #endif // ContextFeatures_h