Looking at the runs of https://build.chromium.org/p/chromium.android/builders/Android%20N5X%20Swarm%20Builder?numbuilds=200

I see sporadic fails of testDatabaseEnabled, for example:

https://build.chromium.org/p/chromium.android/builders/Android%20N5X%20Swarm%20Builder/builds/15391
https://build.chromium.org/p/chromium.android/builders/Android%20N5X%20Swarm%20Builder/builds/15385
https://build.chromium.org/p/chromium.android/builders/Android%20N5X%20Swarm%20Builder/builds/15340

https://build.chromium.org/p/chromium.android/builders/Android%20N5X%20Swarm%20Builder/builds/15263



C  381.806s Main  [FAIL] org.chromium.android_webview.test.AwSettingsTest#testDatabaseEnabled:
C  381.806s Main  org.junit.ComparisonFailure: expected:<[Has databas]e> but was:<[Non]e>
C  381.806s Main  	at org.junit.Assert.assertEquals(Assert.java:115)
C  381.806s Main  	at org.junit.Assert.assertEquals(Assert.java:144)
C  381.806s Main  	at org.chromium.android_webview.test.AwSettingsTest$AwSettingsDatabaseTestHelper.doEnsureSettingHasValue(AwSettingsTest.java:610)
C  381.806s Main  	at org.chromium.android_webview.test.AwSettingsTest$AwSettingsDatabaseTestHelper.doEnsureSettingHasValue(AwSettingsTest.java:572)
C  381.806s Main  	at org.chromium.android_webview.test.AwSettingsTest$AwSettingsTestHelper.ensureSettingHasValue(AwSettingsTest.java:162)
C  381.806s Main  	at org.chromium.android_webview.test.AwSettingsTest$AwSettingsTestHelper.ensureSettingHasAlteredValue(AwSettingsTest.java:110)
C  381.806s Main  	at org.chromium.android_webview.test.AwSettingsTest.testDatabaseEnabled(AwSettingsTest.java:1829)
C  381.806s Main  	at java.lang.reflect.Method.invoke(Native Method)
C  381.806s Main  	at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
C  381.806s Main  	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
C  381.806s Main  	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:52)
C  381.807s Main  	at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
C  381.807s Main  	at org.chromium.base.test.ScreenshotOnFailureStatement.evaluate(ScreenshotOnFailureStatement.java:37)
C  381.807s Main  	at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
C  381.807s Main  	at org.chromium.android_webview.test.AwActivityTestRule$1.evaluate(AwActivityTestRule.java:55)
C  381.807s Main  	at android.support.test.internal.statement.UiThreadStatement.evaluate(UiThreadStatement.java:55)
C  381.807s Main  	at android.support.test.rule.ActivityTestRule$ActivityStatement.evaluate(ActivityTestRule.java:270)
C  381.807s Main  	at org.junit.rules.RunRules.evaluate(RunRules.java:20)
C  381.807s Main  	at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
C  381.807s Main  	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
C  381.807s Main  	at org.chromium.base.test.BaseJUnit4ClassRunner.runChild(BaseJUnit4ClassRunner.java:175)
C  381.807s Main  	at org.chromium.android_webview.test.AwJUnit4ClassRunner.runChild(AwJUnit4ClassRunner.java:61)
C  381.807s Main  	at org.chromium.android_webview.test.AwJUnit4ClassRunner.runChild(AwJUnit4ClassRunner.java:28)
C  381.807s Main  	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
C  381.807s Main  	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
C  381.808s Main  	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
C  381.808s Main  	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
C  381.808s Main  	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
C  381.808s Main  	at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
C  381.808s Main  	at org.chromium.base.test.BaseJUnit4ClassRunner.run(BaseJUnit4ClassRunner.java:164)
C  381.808s Main  	at org.junit.runners.Suite.runChild(Suite.java:128)
C  381.808s Main  	at org.junit.runners.Suite.runChild(Suite.java:27)
C  381.808s Main  	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
C  381.808s Main  	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
C  381.808s Main  	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
C  381.808s Main  	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
C  381.808s Main  	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
C  381.808s Main  	at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
C  381.808s Main  	at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
C  381.808s Main  	at org.junit.runner.JUnitCore.run(JUnitCore.java:115)
C  381.808s Main  	at android.support.test.internal.runner.TestExecutor.execute(TestExecutor.java:59)
C  381.808s Main  	at android.support.test.runner.AndroidJUnitRunner.onStart(AndroidJUnitRunner.java:262)
C  381.809s Main  	at org.chromium.base.test.BaseChromiumAndroidJUnitRunner.onStart(BaseChromiumAndroidJUnitRunner.java:98)
C  381.809s Main  	at android.app.Instrumentation$InstrumentationThread.run(Instrumentation.java:1879)
C  381.809s Main  
C  381.809s Main  Searching for native crashes in: /b/swarming/w/itvdETVU/tmpJKfYjj
C  381.809s Main  Unknown Android release, consider passing --packed-lib.
C  381.809s Main  Reading Android symbols from: /b/swarming/w/ir
C  381.809s Main  Searching for Chrome symbols from within: /b/swarming/w/ir/out/Release/lib.unstripped:/b/swarming/w/ir/out/Release/lib:/b/swarming/w/ir/out/Release