Flakiness dashboard shows it passes on retry; it just crashes when run after the other tests in the suite.

https://test-results.appspot.com/dashboards/flakiness_dashboard.html#testType=extensions_unittests&tests=RendererStartupHelperTest.ExtensionInIncognitoRenderer

$ out_linux/rel/extensions_unittests --gtest_filter=RendererStartupHelperTest.\*
Additional test environment:
    CHROME_DEVEL_SANDBOX=/usr/local/sbin/chrome-devel-sandbox
    CHROME_HEADLESS=1
    LANG=en_US.UTF-8
Command: out_linux/rel/extensions_unittests  --gtest_filter=RendererStartupHelperTest.*

IMPORTANT DEBUGGING NOTE: batches of tests are run inside their
own process. For debugging a test inside a debugger, use the
--gtest_filter=<your_test_name> flag along with
--single-process-tests.
Using sharding settings from environment. This is shard 0/1
Using 1 parallel jobs.
Note: Google Test filter = RendererStartupHelperTest.NormalExtensionLifecycle:RendererStartupHelperTest.EnabledBeforeProcessInitialized:RendererStartupHelperTest.LoadTheme:RendererStartupHelperTest.ExtensionInIncognitoRenderer:RendererStartupHelperTest.PlatformAppInIncognitoRenderer
[==========] Running 5 tests from 1 test case.
[----------] Global test environment set-up.
[----------] 5 tests from RendererStartupHelperTest
[ RUN      ] RendererStartupHelperTest.NormalExtensionLifecycle
[       OK ] RendererStartupHelperTest.NormalExtensionLifecycle (18 ms)
[ RUN      ] RendererStartupHelperTest.EnabledBeforeProcessInitialized
[       OK ] RendererStartupHelperTest.EnabledBeforeProcessInitialized (0 ms)
[ RUN      ] RendererStartupHelperTest.LoadTheme
[       OK ] RendererStartupHelperTest.LoadTheme (0 ms)
[ RUN      ] RendererStartupHelperTest.ExtensionInIncognitoRenderer
[202183:202183:1218/122853.003368:4849630334493:FATAL:dependency_manager.cc(108)] Check failed: false. Attempted to access a context that was ShutDown(). This is most likely a heap smasher in progress. After KeyedService::Shutdown() completes, your service MUST NOT refer to depended services again.
#0 0x00000341b6dc base::debug::StackTrace::StackTrace()
#1 0x00000343950c logging::LogMessage::~LogMessage()
#2 0x000004b36d7b DependencyManager::AssertContextWasntDestroyed()
#3 0x000004b366e2 BrowserContextKeyedServiceFactory::GetContextToUse()
#4 0x000004b3851a KeyedServiceFactory::GetServiceForContext()
#5 0x0000032a1dcf extensions::util::IsIncognitoEnabled()
#6 0x0000032c341d extensions::RendererStartupHelper::OnExtensionLoaded()
#7 0x0000015ae72b extensions::RendererStartupHelperTest_ExtensionInIncognitoRenderer_Test::TestBody()
#8 0x0000026358b6 testing::Test::Run()
#9 0x0000026362d0 testing::TestInfo::Run()
#10 0x0000026367b7 testing::TestCase::Run()
#11 0x00000263ce57 testing::internal::UnitTestImpl::RunAllTests()
#12 0x00000263caa7 testing::UnitTest::Run()
#13 0x000003387e82 base::TestSuite::Run()
#14 0x00000338a817 base::(anonymous namespace)::LaunchUnitTestsInternal()
#15 0x00000338a68b base::LaunchUnitTests()
#16 0x00000148b1a3 main
#17 0x7f9be101bf45 __libc_start_main
#18 0x00000148b02a _start

[202180:202182:1218/122853.113495:4849630444762:ERROR:kill_posix.cc(84)] Unable to terminate process group 202183: No such process (3)
[1/5] RendererStartupHelperTest.NormalExtensionLifecycle (18 ms)
[2/5] RendererStartupHelperTest.EnabledBeforeProcessInitialized (0 ms)
[3/5] RendererStartupHelperTest.LoadTheme (0 ms)
[4/5] RendererStartupHelperTest.ExtensionInIncognitoRenderer (CRASHED)
Note: Google Test filter = RendererStartupHelperTest.PlatformAppInIncognitoRenderer
[==========] Running 1 test from 1 test case.
[----------] Global test environment set-up.
[----------] 1 test from RendererStartupHelperTest
[ RUN      ] RendererStartupHelperTest.PlatformAppInIncognitoRenderer
[       OK ] RendererStartupHelperTest.PlatformAppInIncognitoRenderer (24 ms)
[----------] 1 test from RendererStartupHelperTest (24 ms total)

[----------] Global test environment tear-down
[==========] 1 test from 1 test case ran. (25 ms total)
[  PASSED  ] 1 test.
[5/5] RendererStartupHelperTest.PlatformAppInIncognitoRenderer (24 ms)
1 test crashed:
    RendererStartupHelperTest.ExtensionInIncognitoRenderer (../../extensions/browser/renderer_startup_helper_unittest.cc:282)
Tests took 0 seconds.