[sensors] Accelerometer sensor bindings implementation

third_party/WebKit/Source/modules/sensor/Accelerometer.idl

 // Copyright 2016 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.
 
 // Specification at:
-// https://w3c.github.io/ambient-light/#ambient-light-sensor-interface
+// https://w3c.github.io/accelerometer/#accelerometer-interface
 
 [
     RuntimeEnabled=Sensor,
-    Constructor(optional SensorOptions sensorOptions),
+    Constructor(optional AccelerometerOptions sensorOptions),
     ConstructorCallWith=ScriptState,
     RaisesException=Constructor,
-] interface AmbientLightSensor : Sensor {
-    readonly attribute AmbientLightSensorReading? reading;
+] interface Accelerometer : Sensor {
+    readonly attribute AccelerometerReading? reading;
+    readonly attribute boolean includesGravity;
 };