WIP : Generic Sensor API implementation

device/sensors/android/java/src/org/chromium/device/sensors/SensorStateObserver.java

Index: device/sensors/android/java/src/org/chromium/device/sensors/SensorStateObserver.java
diff --git a/device/sensors/android/java/src/org/chromium/device/sensors/SensorStateObserver.java b/device/sensors/android/java/src/org/chromium/device/sensors/SensorStateObserver.java
new file mode 100644
index 0000000000000000000000000000000000000000..b463f5afb10bf4ca454f15969ff10ae4b58c4a92
--- /dev/null
+++ b/device/sensors/android/java/src/org/chromium/device/sensors/SensorStateObserver.java
@@ -0,0 +1,16 @@
+// 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.
+
+package org.chromium.device.sensors;
+
+/**
+ * Interface for observing state of a sensor, used by factory to remove unused sensors.
+ */
+interface SensorStateObserver {
+
+    /**
+     * Sensor is not in use.
+     */
+    void onSensorNotInUse(SensorBase sensor);
+}