Use chromeos accelerometer reader and support only lid accelerometer.

chromeos/accelerometer/accelerometer_reader.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 CHROMEOS_ACCELEROMETER_ACCELEROMETER_READER_H_
 #define CHROMEOS_ACCELEROMETER_ACCELEROMETER_READER_H_
 
-#include <vector>
-
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "base/observer_list.h"
 #include "chromeos/chromeos_export.h"
 #include "ui/accelerometer/accelerometer_types.h"
 
 namespace base {
 class TaskRunner;
 }
 
 namespace chromeos {
 
 // Reads an accelerometer device and reports data back to an
 // AccelerometerDelegate.
 class CHROMEOS_EXPORT AccelerometerReader {
  public:
   // Configuration structure for accelerometer device.
   struct ConfigurationData {
     ConfigurationData();
     ~ConfigurationData();
 
-    // Scale of accelerometers (i.e. raw value * 1.0f / scale = G's).
-    unsigned int base_scale;
-    unsigned int lid_scale;
+    // Number of accelerometers on device.
+    size_t count;
+
+    // Length of accelerometer updates.
+    size_t length;
+
+    // Which accelerometers are present on device.
+    bool has[ui::ACCELEROMETER_SOURCE_COUNT];
+
+    // Scale of accelerometers (i.e. raw value * scale = m/s^2).
+    float scale[ui::ACCELEROMETER_SOURCE_COUNT][3];
 
     // Index of each accelerometer axis in data stream.
-    std::vector<unsigned int> index;
+    int index[ui::ACCELEROMETER_SOURCE_COUNT][3];
   };
   typedef base::RefCountedData<ConfigurationData> Configuration;
   typedef base::RefCountedData<char[12]> Reading;
 
   // An interface to receive data from the AccelerometerReader.
   class Delegate {
    public:
     virtual void HandleAccelerometerUpdate(
         const ui::AccelerometerUpdate& update) = 0;
   };
 
-  AccelerometerReader(base::TaskRunner* blocking_task_runner,
+  AccelerometerReader(base::TaskRunner* file_task_runner,
                       Delegate* delegate);
   ~AccelerometerReader();
 
  private:
   // Dispatched when initialization is complete. If |success|, |configuration|
   // provides the details of the detected accelerometer.
   void OnInitialized(scoped_refptr<Configuration> configuration, bool success);
 
   // Triggers an asynchronous read from the accelerometer, signalling
   // OnDataRead with the result.
@@ skipping 17 matching lines @@
   scoped_refptr<Configuration> configuration_;
 
   base::WeakPtrFactory<AccelerometerReader> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(AccelerometerReader);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROMEOS_ACCELEROMETER_ACCELEROMETER_READER_H_