[Sensors] Align sensor reading attribute implementation with the specification

third_party/WebKit/Source/modules/sensor/SensorReadingEvent.h

-// Copyright 2016 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef SensorReadingEvent_h
-#define SensorReadingEvent_h
-
-#include "modules/EventModules.h"
-#include "modules/sensor/SensorReading.h"
-#include "modules/sensor/SensorReadingEventInit.h"
-#include "platform/heap/Handle.h"
-
-namespace blink {
-
-class SensorReadingEvent : public Event {
-  DEFINE_WRAPPERTYPEINFO();
-
- public:
-  static SensorReadingEvent* create(const AtomicString& eventType,
-                                    SensorReading* reading) {
-    return new SensorReadingEvent(eventType, reading);
-  }
-
-  static SensorReadingEvent* create(const AtomicString& eventType,
-                                    const SensorReadingEventInit& initializer) {
-    return new SensorReadingEvent(eventType, initializer);
-  }
-
-  ~SensorReadingEvent() override;
-
-  const SensorReading* reading() const { return m_reading.get(); }
-  SensorReading* reading() { return m_reading.get(); }
-  const AtomicString& interfaceName() const override;
-
-  DECLARE_VIRTUAL_TRACE();
-
- protected:
-  Member<SensorReading> m_reading;
-
- private:
-  SensorReadingEvent(const AtomicString& eventType, SensorReading*);
-  SensorReadingEvent(const AtomicString& eventType,
-                     const SensorReadingEventInit& initializer);
-};
-
-DEFINE_TYPE_CASTS(SensorReadingEvent,
-                  Event,
-                  event,
-                  event->interfaceName() == EventNames::SensorReadingEvent,
-                  event.interfaceName() == EventNames::SensorReadingEvent);
-
-}  // namepsace blink
-
-#endif  // SensorReadingEvent_h