Remove DeviceLightEvent implementation

third_party/WebKit/Source/modules/device_light/DeviceLightDispatcher.cpp

-// Copyright 2014 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.
-
-#include "modules/device_light/DeviceLightDispatcher.h"
-
-#include <cmath>
-
-#include "modules/device_light/DeviceLightController.h"
-#include "public/platform/Platform.h"
-
-namespace {
-double EnsureRoundedLuxValue(double lux) {
-  // Make sure to round the lux value to nearest integer, to
-  // avoid too precise values and hence reduce fingerprinting risk.
-  // The special case when the lux value is infinity (no data can be
-  // provided) is simply returned as is.
-  // TODO(timvolodine): consider reducing the lux value precision further.
-  return std::isinf(lux) ? lux : std::round(lux);
-}
-}  // namespace
-
-namespace blink {
-
-DeviceLightDispatcher& DeviceLightDispatcher::Instance() {
-  DEFINE_STATIC_LOCAL(DeviceLightDispatcher, device_light_dispatcher,
-                      (new DeviceLightDispatcher));
-  return device_light_dispatcher;
-}
-
-DeviceLightDispatcher::DeviceLightDispatcher() : last_device_light_data_(-1) {}
-
-DeviceLightDispatcher::~DeviceLightDispatcher() {}
-
-DEFINE_TRACE(DeviceLightDispatcher) {
-  PlatformEventDispatcher::Trace(visitor);
-}
-
-void DeviceLightDispatcher::StartListening() {
-  Platform::Current()->StartListening(kWebPlatformEventTypeDeviceLight, this);
-}
-
-void DeviceLightDispatcher::StopListening() {
-  Platform::Current()->StopListening(kWebPlatformEventTypeDeviceLight);
-  last_device_light_data_ = -1;
-}
-
-void DeviceLightDispatcher::DidChangeDeviceLight(double value) {
-  double newValue = EnsureRoundedLuxValue(value);
-  if (last_device_light_data_ != newValue) {
-    last_device_light_data_ = newValue;
-    NotifyControllers();
-  }
-}
-
-double DeviceLightDispatcher::LatestDeviceLightData() const {
-  return last_device_light_data_;
-}
-
-}  // namespace blink