Pass implementation object to supplemental classes by reference

Source/modules/device_orientation/DeviceMotionController.cpp

 /*
  * Copyright 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2012 Samsung Electronics. 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 copyright
@@ skipping 19 matching lines @@
 #include "RuntimeEnabledFeatures.h"
 #include "core/dom/Document.h"
 #include "core/events/ThreadLocalEventNames.h"
 #include "core/page/Page.h"
 #include "modules/device_orientation/DeviceMotionData.h"
 #include "modules/device_orientation/DeviceMotionDispatcher.h"
 #include "modules/device_orientation/DeviceMotionEvent.h"
 
 namespace WebCore {
 
-DeviceMotionController::DeviceMotionController(Document* document)
+DeviceMotionController::DeviceMotionController(Document& document)
     : DeviceSensorEventController(document)
-    , DOMWindowLifecycleObserver(document->domWindow())
+    , DOMWindowLifecycleObserver(document.domWindow())
 {
 }
 
 DeviceMotionController::~DeviceMotionController()
 {
     stopUpdating();
 }
 
 void DeviceMotionController::didChangeDeviceMotion(DeviceMotionData* deviceMotionData)
 {
     dispatchDeviceEvent(DeviceMotionEvent::create(EventTypeNames::devicemotion, deviceMotionData));
 }
 
 const char* DeviceMotionController::supplementName()
 {
     return "DeviceMotionController";
 }
 
-DeviceMotionController* DeviceMotionController::from(Document* document)
+DeviceMotionController& DeviceMotionController::from(Document& document)
 {
     DeviceMotionController* controller = static_cast<DeviceMotionController*>(DocumentSupplement::from(document, supplementName()));
     if (!controller) {
         controller = new DeviceMotionController(document);
         DocumentSupplement::provideTo(document, supplementName(), adoptPtr(controller));
     }
-    return controller;
+    return *controller;
 }
 
 bool DeviceMotionController::hasLastData()
 {
     return DeviceMotionDispatcher::instance().latestDeviceMotionData();
 }
 
 PassRefPtr<Event> DeviceMotionController::getLastEvent()
 {
     return DeviceMotionEvent::create(EventTypeNames::devicemotion, DeviceMotionDispatcher::instance().latestDeviceMotionData());
@@ skipping 32 matching lines @@
     }
 }
 
 void DeviceMotionController::didRemoveAllEventListeners(DOMWindow*)
 {
     stopUpdating();
     m_hasEventListener = false;
 }
 
 } // namespace WebCore