Added Network Quality Estimator Real-time interface to Cronet

components/cronet/android/java/src/org/chromium/net/NetworkQualityRTTObserver.java

+// Copyright 2015 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.net;
+
+/**
+ * Interface to watch for observations of round trip times.
+ */
+public interface NetworkQualityRTTObserver {

[miloslav, 2015/09/05 18:52:40]

The rest of Cronet uses "Acronyms as words":
https://source.android.com/source/code-style.html#treat-acronyms-as-words. It is
also in the google3 style guide, so "Rtt" instead of "RTT" would be better (also
in a number of other places).

[bengr, 2015/09/14 21:04:35]

Done.

+    /**
+     * Reports a new round trip time observation. This is called on the network thread, so the
+     * observer should exit quickly.
+     * @param rttMs The round trip time in milliseconds.
+     * @param whenMs The time since the epoch in milliseconds.
+     * @param source The observation source from {@link NetworkQualityObservationSource}.

[pauljensen, 2015/09/02 16:54:48]

So I do love GENERATED_JAVA_ENUM_PACKAGE...but I'm not sure if it translates C++
comments to Java comments.  If it doesn't that's kinda a deal-breaker here as we
need high quality javadocs for Cronet's APIs.

[bengr, 2015/09/14 21:04:35]

Let's leave it as is here, until we're more confident that this is the right way
to expose the source, and then I'll stop using GENERATED_JAVA_ENUM_PACKAGE if
needed.

+     */
+    public void onRTTObservation(int rttMs, long whenMs, int source);
+}