[sensors] Android platform adaptation for Generic Sensor API

device/generic_sensor/android/java/src/org/chromium/device/sensors/PlatformSensorNotifier.java

+// 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 used to notify native PlatformSensor about sensor reading changes or errors.
+ */
+interface PlatformSensorNotifier {

[timvolodine, 2016/09/07 14:51:06]

Looking at the delta wrt the latest upload, looks like you've silently added the
PlatformSensorNotifier class? 

Maybe this is a small change, but in general (significant) changes after reviews
are best done in follow-up patches, or at least please provide explanation when
uploading a new patch.

[shalamov, 2016/09/07 18:49:18]

Unfurtunately this is required by to abstract native methods in PlatformSensor,
since Mockito cannot mock native methods. Without this interface important parts
of PlatformSensor cannot be tested, e.g. OnSensorChanged, fillBuffer, exceptions
and notifications to platform side. You have more experience with java code,
maybe there is a better way to mock native methods?

[timvolodine, 2016/09/08 12:51:03]

oh sorry I didn't realize it was for testing only.. If that's the case maybe try
to encapsulate this interface inside the test or the PlatformSensor itself if
possible. I was assuming this was some new 'functionality' or refactoring. Also
see Ted's comment.

[shalamov, 2016/09/08 13:40:49]

Done.

+    // Called when sensor reading is changed.
+    public void sensorReadingChanged();

[Ted C, 2016/09/07 18:12:24]

public is standard on interfaces, so you don't actually need this.

But, I question whether we actually need this.  Seems like we could isolate this
in the test code:

something along the lines of:

TestPlatformSensor extends PlatformSensor {

    

    @Override
    public void sensorReadingChanged() {
        // testing code
    }

    @Override
    public void sensorError() {
        // testing code
    }

}

If we can do something like that, we're reducing the clutter of the
production code.

+    // Called in case of error.
+    public void sensorError();
+}