[DeviceLight] Add renderer+common parts

content/renderer/device_sensors/device_light_event_pump.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 CONTENT_RENDERER_DEVICE_SENSORS_DEVICE_LIGHT_EVENT_PUMP_H_
+#define CONTENT_RENDERER_DEVICE_SENSORS_DEVICE_LIGHT_EVENT_PUMP_H_
+
+#include "base/memory/scoped_ptr.h"
+#include "content/common/device_sensors/device_light_data.h"
+#include "content/renderer/device_sensors/device_sensor_event_pump.h"
+#include "content/renderer/shared_memory_seqlock_reader.h"
+
+namespace blink {
+class WebDeviceLightListener;
+}
+
+namespace content {
+
+typedef SharedMemorySeqLockReader<DeviceLightData>
+    DeviceLightSharedMemoryReader;
+
+class CONTENT_EXPORT DeviceLightEventPump : public DeviceSensorEventPump {
+ public:
+  DeviceLightEventPump();
+  explicit DeviceLightEventPump(int pump_delay_millis);
+  virtual ~DeviceLightEventPump();
+
+  // Sets the listener to receive updates for device light data at
+  // regular intervals. Returns true if the registration was successful.
+  bool SetListener(blink::WebDeviceLightListener* listener);
+
+  // RenderProcessObserver implementation.
+  virtual bool OnControlMessageReceived(const IPC::Message& message) OVERRIDE;
+
+ protected:
+  // Methods overriden from base class DeviceSensorEventPump
+  virtual void FireEvent() OVERRIDE;
+  virtual bool InitializeReader(base::SharedMemoryHandle handle) OVERRIDE;
+  virtual bool SendStartMessage() OVERRIDE;
+  virtual bool SendStopMessage() OVERRIDE;
+
+  // Default delay between subsequent firing of DeviceLight events.
+  static const int kDefaultLightPumpDelayMillis;

[jochen (gone - plz use gerrit), 2014/06/25 13:16:11]

that value is not used anywhere outside of the .cc file as far as I can see, so
it doesn't need to be on the class at all.

You can just define a const int in an anonymous namespace inside the cc file

[riju_, 2014/06/25 15:53:11]

Done.

+
+  blink::WebDeviceLightListener* listener_;
+  scoped_ptr<DeviceLightSharedMemoryReader> reader_;
+  double last_seen_data_;
+
+  DISALLOW_COPY_AND_ASSIGN(DeviceLightEventPump);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_RENDERER_DEVICE_SENSORS_DEVICE_LIGHT_EVENT_PUMP_H_