Generalize and refactor DeviceSensorEvent* architecture to support multi-event type targets.

Source/modules/device_orientation/DeviceMotionDispatcher.h

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 13 matching lines @@
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef DeviceMotionDispatcher_h
 #define DeviceMotionDispatcher_h
 
-#include "core/frame/DeviceSensorEventDispatcher.h"
+#include "core/frame/DeviceEventDispatcherBase.h"
 #include "platform/heap/Handle.h"
 #include "public/platform/WebDeviceMotionListener.h"
 #include "wtf/RefPtr.h"
 
 namespace blink {
 class WebDeviceMotionData;
 }
 
 namespace WebCore {
 
 class DeviceMotionController;
 class DeviceMotionData;
 
-// This class listens to device motion data and dispatches it to all
-// listening controllers.
-class DeviceMotionDispatcher FINAL : public DeviceSensorEventDispatcher, public blink::WebDeviceMotionListener {
+// This class listens to device motion data and notifies all registered controllers.
+class DeviceMotionDispatcher FINAL : public DeviceEventDispatcherBase, public blink::WebDeviceMotionListener {
 public:
     static DeviceMotionDispatcher& instance();
 
     // Note that the returned object is owned by this class.
     // FIXME: make the return value const, see crbug.com/233174.
     DeviceMotionData* latestDeviceMotionData();
 
-    // This method is called every time new device motion data is available.
+    // Inherited from WebDeviceMotionListener.
     virtual void didChangeDeviceMotion(const blink::WebDeviceMotionData&) OVERRIDE;
-    void addDeviceMotionController(DeviceMotionController*);
-    void removeDeviceMotionController(DeviceMotionController*);
 
 private:
     DeviceMotionDispatcher();
     virtual ~DeviceMotionDispatcher();
 
+    // Inherited from DeviceEventDispatcherBase.
     virtual void startListening() OVERRIDE;
     virtual void stopListening() OVERRIDE;
 
     RefPtrWillBePersistent<DeviceMotionData> m_lastDeviceMotionData;
 };
 
 } // namespace WebCore
 
 #endif // DeviceMotionDispatcher_h