I'm seeing failures on an internal bot that look like this:
	at junit.framework.Assert.assertTrue(Assert.java:27)
	at org.chromium.net.QuicTest.testRealTimeNetworkQualityObservationsWithQuic(QuicTest.java:197)
It doesn't look like this test properly waits for the TestNetworkQualityRttListener to receive its callback.

I can reproduce this locally with a CL I made to demonstrate the issue: https://codereview.chromium.org/2849093003
C   27.654s Main  ********************************************************************************
C   27.654s Main  Detailed Logs
C   27.654s Main  ********************************************************************************
C   27.654s Main  [FAIL] org.chromium.net.QuicTest#testRealTimeNetworkQualityObservationsWithQuic:
C   27.654s Main  java.lang.Throwable: CronetTestBase#runTest failed.
C   27.654s Main        at org.chromium.net.CronetTestBase.runTest(CronetTestBase.java:147)
C   27.655s Main        at android.test.AndroidTestRunner.runTest(AndroidTestRunner.java:191)
C   27.655s Main        at android.test.AndroidTestRunner.runTest(AndroidTestRunner.java:176)
C   27.655s Main        at android.test.InstrumentationTestRunner.onStart(InstrumentationTestRunner.java:555)
C   27.655s Main        at android.app.Instrumentation$InstrumentationThread.run(Instrumentation.java:1959)
C   27.655s Main  Caused by: junit.framework.AssertionFailedError
C   27.655s Main        at org.chromium.net.QuicTest.testRealTimeNetworkQualityObservationsWithQuic(QuicTest.java:200)
C   27.655s Main        at org.chromium.net.CronetTestBase.runTest(CronetTestBase.java:133)
C   27.655s Main        ... 9 more
C   27.655s Main  ********************************************************************************
C   27.655s Main  Summary
C   27.655s Main  ********************************************************************************
C   27.655s Main  [==========] 1 test ran.
C   27.655s Main  [  PASSED  ] 0 tests.
C   27.656s Main  [  FAILED  ] 1 test, listed below:
C   27.656s Main  [  FAILED  ] org.chromium.net.QuicTest#testRealTimeNetworkQualityObservationsWithQuic
C   27.656s Main  
C   27.656s Main  1 FAILED TEST
C   27.656s Main  ********************************************************************************