Implement DeviceLight

Source/modules/device_light/DeviceLightDispatcher.h

+// 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.
+
+#ifndef DeviceLightDispatcher_h
+#define DeviceLightDispatcher_h
+
+// TODO(riju) make DeviceSensorEventDispatcher.h common to all Device Apis
+//  by extracting it out of device_orientation
+#include "modules/device_orientation/DeviceSensorEventDispatcher.h"
+#include "public/platform/WebDeviceLightListener.h"
+#include "wtf/RefPtr.h"
+
+namespace WebCore {
+
+class DeviceLightController;
+
+// This class listens to device light data and dispatches it to all
+// listening controllers
+class DeviceLightDispatcher : public DeviceSensorEventDispatcher, public blink::WebDeviceLightListener {

[Inactive, 2014/03/07 19:29:52]

Can be marked as FINAL

[riju_, 2014/03/10 16:17:26]

Done.

+public:
+    static DeviceLightDispatcher& instance();
+
+    double latestDeviceLightData();
+
+    // This method is called every time new device light data is available.
+    virtual void didChangeDeviceLight(const double&) OVERRIDE;

[Inactive, 2014/03/07 19:29:52]

const double& -> double?

[riju_, 2014/03/10 16:17:26]

Done.

+    void addDeviceLightController(DeviceLightController*);
+    void removeDeviceLightController(DeviceLightController*);
+
+private:
+    DeviceLightDispatcher();
+    ~DeviceLightDispatcher();

[Inactive, 2014/03/07 19:29:52]

virtual

[riju_, 2014/03/10 16:17:26]

Done.

+
+    virtual void startListening() OVERRIDE;
+    virtual void stopListening() OVERRIDE;
+
+    double m_lastDeviceLightData;
+};
+
+} // namespace WebCore
+
+#endif // DeviceLightDispatcher_h