Disable the flaky NetworkQualityEstimator unittest on ios_simulator

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 1348 matching lines @@
     base::RunLoop().Run();
 
     EXPECT_EQ(test.allow_small_localhost_requests,
               estimator.GetRecentHttpRTT(base::TimeTicks(), &rtt));
     EXPECT_EQ(
         test.allow_small_localhost_requests,
         estimator.GetRecentDownlinkThroughputKbps(base::TimeTicks(), &kbps));
   }
 }
 
+#if defined(OS_IOS)
+// Flaky on iOS: crbug.com/672917.
+#define MAYBE_TestEffectiveConnectionTypeObserver \
+  DISABLED_TestEffectiveConnectionTypeObserver
+#else
+#define MAYBE_TestEffectiveConnectionTypeObserver \
+  TestEffectiveConnectionTypeObserver
+#endif
+
 // Tests that the effective connection type is computed at the specified
 // interval, and that the observers are notified of any change.
-TEST(NetworkQualityEstimatorTest, TestEffectiveConnectionTypeObserver) {
+TEST(NetworkQualityEstimatorTest, MAYBE_TestEffectiveConnectionTypeObserver) {
   base::HistogramTester histogram_tester;
   std::unique_ptr<base::SimpleTestTickClock> tick_clock(
       new base::SimpleTestTickClock());
   base::SimpleTestTickClock* tick_clock_ptr = tick_clock.get();
 
   TestEffectiveConnectionTypeObserver observer;
   std::map<std::string, std::string> variation_params;
   TestNetworkQualityEstimator estimator(variation_params);
   estimator.AddEffectiveConnectionTypeObserver(&observer);
   estimator.SetTickClockForTesting(std::move(tick_clock));
@@ skipping 1084 matching lines @@
       request->Start();
       base::RunLoop().Run();
 
       EXPECT_EQ(effective_connection_type,
                 estimator.GetEffectiveConnectionType());
     }
   }
 }
 
 }  // namespace net