Refactors DeviceOrientation to make it more extensible

content/browser/device_orientation/data_fetcher.h

 // Copyright (c) 2012 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_BROWSER_DEVICE_ORIENTATION_DATA_FETCHER_H_
 #define CONTENT_BROWSER_DEVICE_ORIENTATION_DATA_FETCHER_H_
 
+#include "content/browser/device_orientation/device_data.h"
+
 namespace device_orientation {
 
-class Orientation;
-
 class DataFetcher {
  public:
   virtual ~DataFetcher() {}
 
-  // Returns false if there was a fatal error getting the orientation.
-  // Returns true otherwise. If the fetcher has orientation data available
-  // it will fill it in, otherwise the argument will be unaltered.
-  virtual bool GetOrientation(Orientation*) = 0;
+  // Returns NULL if there was a fatal error getting the device data of this
+  // type or if this fetcher can never provide this type of data. Otherwise,
+  // returns a pointer to a DeviceData containing the most recent data.
+  virtual const DeviceData* GetDeviceData(DeviceData::Type type) = 0;
 };
 
 }  // namespace device_orientation
 
 #endif  // CONTENT_BROWSER_DEVICE_ORIENTATION_DATA_FETCHER_H_