Enable NQE when Cronet Engine is built

components/cronet/android/test/javatests/src/org/chromium/net/TestNetworkQualityThroughputListener.java

Index: components/cronet/android/test/javatests/src/org/chromium/net/TestNetworkQualityThroughputListener.java
diff --git a/components/cronet/android/test/javatests/src/org/chromium/net/TestNetworkQualityThroughputListener.java b/components/cronet/android/test/javatests/src/org/chromium/net/TestNetworkQualityThroughputListener.java
new file mode 100644
index 0000000000000000000000000000000000000000..c4574a50f537fef4ac8026912a7173340a22aa69
--- /dev/null
+++ b/components/cronet/android/test/javatests/src/org/chromium/net/TestNetworkQualityThroughputListener.java
@@ -0,0 +1,51 @@
+// 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.net;
+
+import static junit.framework.Assert.assertEquals;
+
+import android.os.ConditionVariable;
+
+import java.util.concurrent.Executor;
+
+class TestNetworkQualityThroughputListener extends NetworkQualityThroughputListener {
+    // Lock to ensure that observation counts can be updated and read by different threads.
+    private final Object mLock = new Object();
+    private final ConditionVariable mWaitForThroughput;
+    private int mThroughputObservationCount;
+    private Thread mExecutorThread;
+
+    TestNetworkQualityThroughputListener(Executor executor, ConditionVariable waitForThroughput) {
+        super(executor);
+        mWaitForThroughput = waitForThroughput;
+    }
+
+    @Override
+    public void onThroughputObservation(int throughputKbps, long when, int source) {
+        synchronized (mLock) {
+            if (mWaitForThroughput != null) {
+                mWaitForThroughput.open();
+            }
+            mThroughputObservationCount++;
+            if (mExecutorThread == null) {
+                mExecutorThread = Thread.currentThread();
+            }
+            // Verify that the listener is always notified on the same thread.
+            assertEquals(mExecutorThread, Thread.currentThread());
+        }
+    }
+
+    public int throughputObservationCount() {
+        synchronized (mLock) {
+            return mThroughputObservationCount;
+        }
+    }
+
+    public Thread getThread() {
+        synchronized (mLock) {
+            return mExecutorThread;
+        }
+    }
+}