NQE: Add net log event if the metric changes substantially

net/nqe/network_quality_estimator_unittest.cc

 // 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.
 
 #include "net/nqe/network_quality_estimator.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <limits>
@@ skipping 393 matching lines @@
   TestEffectiveConnectionTypeObserver observer;
   estimator.AddEffectiveConnectionTypeObserver(&observer);
   TestRTTObserver rtt_observer;
   estimator.AddRTTObserver(&rtt_observer);
   TestThroughputObserver throughput_observer;
   estimator.AddThroughputObserver(&throughput_observer);
 
   // |observer| should be notified as soon as it is added.
   base::RunLoop().RunUntilIdle();
   EXPECT_EQ(1U, observer.effective_connection_types().size());
-  EXPECT_EQ(
+  EXPECT_LE(

[RyanSturm, 2017/03/03 22:10:21]

why is this LE now?

[tbansal1, 2017/03/03 23:06:35]

With this CL, it is difficult to precisely determine the number of entries that
will be added to the net log.

       2, estimator.GetEntriesCount(NetLogEventType::NETWORK_QUALITY_CHANGED));
 
   estimator.SimulateNetworkChange(
       NetworkChangeNotifier::ConnectionType::CONNECTION_2G, "test");
   histogram_tester.ExpectBucketCount(
       "NQE.RTT.ObservationSource",
       NETWORK_QUALITY_OBSERVATION_SOURCE_HTTP_CACHED_ESTIMATE, 1);
   histogram_tester.ExpectBucketCount(
       "NQE.Kbps.ObservationSource",
       NETWORK_QUALITY_OBSERVATION_SOURCE_HTTP_CACHED_ESTIMATE, 1);
@@ skipping 2689 matching lines @@
 
   // Cleanup.
   estimator.RemoveRTTObserver(&rtt_observer);
   estimator.RemoveThroughputObserver(&throughput_observer);
   estimator.RemoveRTTAndThroughputEstimatesObserver(&rtt_throughput_observer);
   estimator.RemoveEffectiveConnectionTypeObserver(
       &effective_connection_type_observer);
 }
 
 }  // namespace net