Pass implementation object to supplemental classes by reference

Source/core/dom/ContextFeatures.cpp

 /*
  * 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 66 matching lines @@
     if (!document)
         return true;
     return document->contextFeatures()->isEnabled(document, MutationEvents, true);
 }
 
 bool ContextFeatures::pushStateEnabled(Document* document)
 {
     return document->contextFeatures()->isEnabled(document, PushState, true);
 }
 
-void provideContextFeaturesTo(Page* page, ContextFeaturesClient* client)
+void provideContextFeaturesTo(Page& page, ContextFeaturesClient* client)
 {
     RefCountedSupplement<Page, ContextFeatures>::provideTo(page, ContextFeatures::supplementName(), ContextFeatures::create(client));
 }
 
-void provideContextFeaturesToDocumentFrom(Document* document, Page* page)
+void provideContextFeaturesToDocumentFrom(Document& document, Page& page)
 {
     ContextFeatures* provided = static_cast<ContextFeatures*>(RefCountedSupplement<Page, ContextFeatures>::from(page, ContextFeatures::supplementName()));
     if (!provided)
         return;
-    document->setContextFeatures(provided);
+    document.setContextFeatures(provided);
 }
 
 }