Pass implementation object to supplemental classes by reference

Source/core/html/imports/HTMLImportsController.cpp

 /*
  * Copyright (C) 2013 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.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 20 matching lines @@
 #include "config.h"
 #include "core/html/imports/HTMLImportsController.h"
 
 #include "core/dom/Document.h"
 #include "core/fetch/ResourceFetcher.h"
 #include "core/html/imports/HTMLImportChild.h"
 #include "core/html/imports/HTMLImportChildClient.h"
 
 namespace WebCore {
 
-void HTMLImportsController::provideTo(Document* master)
+void HTMLImportsController::provideTo(Document& master)
 {
     DEFINE_STATIC_LOCAL(const char*, name, ("HTMLImportsController"));
     OwnPtr<HTMLImportsController> controller = adoptPtr(new HTMLImportsController(master));
-    master->setImport(controller.get());
+    master.setImport(controller.get());
     DocumentSupplement::provideTo(master, name, controller.release());
 }
 
-HTMLImportsController::HTMLImportsController(Document* master)
-    : m_master(master)
+HTMLImportsController::HTMLImportsController(Document& master)
+    : m_master(&master)
     , m_recalcTimer(this, &HTMLImportsController::recalcTimerFired)
 {
     recalcTreeState(this); // This recomputes initial state.
 }
 
 HTMLImportsController::~HTMLImportsController()
 {
     ASSERT(!m_master);
 }
 
@@ skipping 98 matching lines @@
 
 void HTMLImportsController::recalcTimerFired(Timer<HTMLImportsController>*)
 {
     do {
         m_recalcTimer.stop();
         HTMLImport::recalcTreeState(this);
     } while (m_recalcTimer.isActive());
 }
 
 } // namespace WebCore