Implement device_orientation::Provider.

chrome/browser/device_orientation/data_fetcher.h

+// Copyright (c) 2010 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 CHROME_BROWSER_DEVICE_ORIENTATION_DATA_FETCHER_H_
+#define CHROME_BROWSER_DEVICE_ORIENTATION_DATA_FETCHER_H_
+
+namespace device_orientation {
+
+class Orientation;
+
+class DataFetcher {
+ public:
+  virtual ~DataFetcher() {}
+  virtual bool GetOrientation(Orientation*) = 0;
+  virtual int MinSamplingIntervalMs() const { return 0; }
+};
+
+}  // namespace device_orientation
+
+#endif  // CHROME_BROWSER_DEVICE_ORIENTATION_DATA_FETCHER_H_