See https://test-results.appspot.com/dashboards/flakiness_dashboard.html#tests=org.chromium.chrome.browser.payments.PaymentRequestNoShippingTest%23testAddEmptyNameOnCardAndCancel&testType=chrome_public_test_apk

low-end failure from https://build.chromium.org/p/chromium.android/builders/Lollipop%20Low-end%20Tester/builds/3793/steps/chrome_public_test_apk/logs/stdio

C 1394.440s Main  [FAIL] org.chromium.chrome.browser.payments.PaymentRequestNoShippingTest#testAddEmptyNameOnCardAndCancel:
C 1394.440s Main  java.util.concurrent.TimeoutException: waitForCallback timed out!
C 1394.440s Main  	at org.chromium.content.browser.test.util.CallbackHelper.waitForCallback(CallbackHelper.java:184)
C 1394.440s Main  	at org.chromium.content.browser.test.util.CallbackHelper.waitForCallback(CallbackHelper.java:192)
C 1394.441s Main  	at org.chromium.content.browser.test.util.CallbackHelper.waitForCallback(CallbackHelper.java:198)
C 1394.441s Main  	at org.chromium.chrome.browser.payments.PaymentRequestTestBase.clickInCardEditorAndWait(PaymentRequestTestBase.java:227)
C 1394.441s Main  	at org.chromium.chrome.browser.payments.PaymentRequestNoShippingTest.testAddEmptyNameOnCardAndCancel(PaymentRequestNoShippingTest.java:125)
C 1394.441s Main  	at android.test.InstrumentationTestCase.runMethod(InstrumentationTestCase.java:214)
C 1394.441s Main  	at android.test.InstrumentationTestCase.runTest(InstrumentationTestCase.java:199)
C 1394.441s Main  	at android.test.ActivityInstrumentationTestCase2.runTest(ActivityInstrumentationTestCase2.java:192)
C 1394.441s Main  	at org.chromium.chrome.test.ChromeActivityTestCaseBase.runTest(ChromeActivityTestCaseBase.java:765)
C 1394.441s Main  	at org.chromium.base.test.BaseTestResult.runParameterized(BaseTestResult.java:161)
C 1394.441s Main  	at org.chromium.base.test.BaseTestResult.run(BaseTestResult.java:124)
C 1394.441s Main  	at android.test.AndroidTestRunner.runTest(AndroidTestRunner.java:191)
C 1394.441s Main  	at android.test.AndroidTestRunner.runTest(AndroidTestRunner.java:176)
C 1394.441s Main  	at android.test.InstrumentationTestRunner.onStart(InstrumentationTestRunner.java:555)
C 1394.441s Main  	at android.app.Instrumentation$InstrumentationThread.run(Instrumentation.java:1853)

Same failure mode for jb: https://build.chromium.org/p/chromium.android/builders/Jelly%20Bean%20Tester/builds/5419/steps/chrome_public_test_apk/logs/stdio


Given that this is limited to the A1s (L low-end) and the N4s (JB), I imagine that this is just an issue of the timeouts being too low. (The L low-end tests are already running w/ --timeout-scale 2)