Implement DeviceLight

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 "config.h"
+#include "modules/device_light/DeviceLightDispatcher.h"
+
+#include "core/frame/DeviceSensorEventDispatcher.h"
+#include "modules/device_light/DeviceLightController.h"
+#include "public/platform/Platform.h"
+#include "wtf/TemporaryChange.h"
+
+namespace WebCore {
+
+DeviceLightDispatcher& DeviceLightDispatcher::instance()
+{
+    DEFINE_STATIC_LOCAL(DeviceLightDispatcher, deviceLightDispatcher, ());
+    return deviceLightDispatcher;
+}
+
+DeviceLightDispatcher::DeviceLightDispatcher() : m_lastDeviceLightData(-1)

[Inactive, 2014/05/09 13:12:47]

nit: Per coding style, I think ": m_lastDeviceLightData(-1)" should be on the
next line.

[riju_, 2014/05/09 13:45:35]

Done.

Tools/Scripts/check-webkit-style (or cpplint.py) did not complain, but checked
the Blink coding doc and found you are right.

+{
+}
+
+DeviceLightDispatcher::~DeviceLightDispatcher()
+{
+}
+
+
+void DeviceLightDispatcher::addDeviceLightController(DeviceLightController* controller)
+{
+    addController(controller);
+}
+
+void DeviceLightDispatcher::removeDeviceLightController(DeviceLightController* controller)
+{
+    removeController(controller);
+}
+
+void DeviceLightDispatcher::startListening()
+{
+    blink::Platform::current()->setDeviceLightListener(this);
+}
+
+void DeviceLightDispatcher::stopListening()
+{
+    blink::Platform::current()->setDeviceLightListener(0);
+    m_lastDeviceLightData = -1;
+}
+
+void DeviceLightDispatcher::didChangeDeviceLight(double value)
+{
+    m_lastDeviceLightData = value;
+
+    {
+        TemporaryChange<bool> changeIsDispatching(m_isDispatching, true);
+        // Don't fire controllers removed or added during event dispatch.
+        size_t size = m_controllers.size();
+        for (size_t i = 0; i < size; ++i) {
+            if (m_controllers[i])
+                static_cast<DeviceLightController*>(m_controllers[i])->didChangeDeviceLight(m_lastDeviceLightData);
+        }
+    }
+
+    if (m_needsPurge)
+        purgeControllers();
+}
+
+double DeviceLightDispatcher::latestDeviceLightData() const
+{
+    return m_lastDeviceLightData;
+}
+
+} // namespace WebCore