The error is:

[ RUN      ] ChromeNetworkServiceBrowserTest.EncryptedCookies
[6068:5328:0728/094031.810:WARNING:chrome_browser_main_win.cc(654)] Command line too long for RegisterApplicationRestart:  --brave-new-test-launcher --cfi-diag=0 --disable-gpu-process-for-dx12-vulkan-info-collection --gtest_also_run_disabled_tests --gtest_filter=ChromeNetworkServiceBrowserTest.EncryptedCookies --single_process --test-launcher-bot-mode --test-launcher-output="e:\b\swarm_slave\w\it1mwgaa\scoped_dir4020_27437\results4020_90\test_results.xml" --test-launcher-summary-output="e:\b\swarm_slave\w\io2_roue\output.json" --user-data-dir="e:\b\swarm_slave\w\it1mwgaa\scoped_dir4020_27437\d4020_9157" --disable-offline-auto-reload --no-first-run --no-default-browser-check --enable-logging=stderr --disable-default-apps --wm-window-animations-disabled --disable-component-update --test-type=browser --force-color-profile=srgb --disable-zero-browsers-open-for-tests --ipc-connection-timeout=30 --allow-file-access-from-files --dom-automation --log-gpu-control-list-decisions --disable-backgrounding-occluded-windows --disable-gl-drawing-for-tests --override-use-software-gl-for-tests --force-color-profile=srgb --disable-compositor-ukm-for-tests --enable-features=NetworkService,TestFeatureForBrowserTest1 --disable-features=NetworkPrediction,SpeculativePreconnect,TestFeatureForBrowserTest2 --disable-gpu-process-for-dx12-vulkan-info-collection --flag-switches-begin --flag-switches-end --file-url-path-alias="/gen=e:\b\swarm_slave\w\ir\out\Release\gen" --restore-last-session about:blank
[6068:4856:0728/094031.865:WARNING:discovery_network_list_win.cc(195)] Failed to open Wlan client handle: 1062
[5832:4160:0728/094031.941:INFO:media_foundation_video_encode_accelerator_win.cc(346)] Windows versions earlier than 8 are not supported.
../../chrome/browser/chrome_network_service_browsertest.cc(120): error: Expected equality of these values:
  1u
    Which is: 1
  cookies.size()
    Which is: 0
Stack trace:
Backtrace:
	StackTraceGetter::CurrentStackTrace [0x01A1BA38+40]
	testing::internal::UnitTestImpl::CurrentOsStackTraceExceptTop [0x01A24515+69]
	testing::internal::AssertHelper::operator= [0x01A24160+48]
	std::vector<net::CanonicalCookie,std::allocator<net::CanonicalCookie> >::_Tidy [0x00E21606+550]
	content::BrowserTestBase::ProxyRunTestOnMainThreadLoop [0x03AF2269+441]
	ChromeBrowserMainParts::PreMainMessageLoopRunImpl [0x049282E1+3233]
	ChromeBrowserMainParts::PreMainMessageLoopRun [0x0492757A+170]
	content::BrowserMainLoop::PreMainMessageLoopRun [0x02551F04+68]
	content::StartupTaskRunner::RunAllTasksNow [0x028C986E+30]
	content::BrowserMainLoop::CreateStartupTasks [0x02550CA5+805]
	content::BrowserMainRunnerImpl::Initialize [0x02554234+100]
	content::BrowserMain [0x0254EFDA+138]
	content::RunBrowserProcessMain [0x0383B3D4+84]
	content::ContentMainRunnerImpl::Run [0x0383BC6A+538]
	content::ContentServiceManagerMainDelegate::RunEmbedderProcess [0x0383B053+19]
	service_manager::Main [0x040478D8+1384]
	content::ContentMain [0x0383B323+51]
	content::BrowserTestBase::SetUp [0x03AF1FE6+1942]

Hi Matt, could you take a look?  I could not find a recent change that might make this test flaky.  Thanks.

I'm not at all familiar with the on-disk encryption stuff.  I'll disable the test, though.

Looks like a windows only failure, so I'll try only disabling there.  I think this is the test that tries to read encrypted cookies with encryption disabled, and expects a failure.  So I guess this is SQL failing or taking too long with (effectively) a corrupted cookie store?

Scratch that -  We write a cookie with encryption enabled, and then expect to read it with encryption disabled (Which is supposed to succeed, apparently).

How this works is the encrypted values are written to a different column in the DB than unencrypted values, so when reading encrypted cookies with an unencrypted cookie store, the value for the cookie should just be empty. I'm guessing what's happening is in the PRE part of the test, the cookies do not finish getting written sometimes.

Thanks for the explanation!

[+jam], who wrote the code to wait for clean shutdown of the network service (I assume the relevant task has the BLOCK_SHUTDOWN trait)

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/e254701af11ae522eb7f17d2e94f8261c57949c1

commit e254701af11ae522eb7f17d2e94f8261c57949c1
Author: Matt Menke <mmenke@chromium.org>
Date: Mon Jul 30 16:57:12 2018

Disable ChromeNetworkServiceBrowserTest.EncryptedCookies on Windows.

The test is failing flakily, at least on Win7.

Bug: 868667
Change-Id: If9604610aa51a5754795bc6e5b6b44c06f486af8
Reviewed-on: https://chromium-review.googlesource.com/1155093
Reviewed-by: Clark DuVall <cduvall@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Matt Menke <mmenke@chromium.org>
Cr-Commit-Position: refs/heads/master@{#579071}
[modify] https://crrev.com/e254701af11ae522eb7f17d2e94f8261c57949c1/chrome/browser/chrome_network_service_browsertest.cc

This also seems to fail on Mac-10.11:

https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Mac10.11%20Tests/28843[ RUN      ] ChromeNetworkServiceBrowserTest.EncryptedCookies
[21759:775:0904/102202.149937:ERROR:delegated_frame_host.cc(173)] Not implemented reached in void content::DelegatedFrameHost::SetNeedsBeginFrames(bool)
../../chrome/browser/net/chrome_network_service_browsertest.cc:119: Failure
Expected equality of these values:
  1u
    Which is: 1
  cookies.size()
    Which is: 0
Stack trace:
0   browser_tests                       0x0000000110a3f56b testing::internal::UnitTestImpl::CurrentOsStackTraceExceptTop(int) + 91
1   browser_tests                       0x0000000110a3ef39 testing::internal::AssertHelper::operator=(testing::Message const&) const + 89
2   browser_tests                       0x000000010f70a6a9 content::(anonymous namespace)::ChromeNetworkServiceBrowserTest_EncryptedCookies_Test::RunTestOnMainThread() + 969
3   browser_tests                       0x00000001131cddeb content::BrowserTestBase::ProxyRunTestOnMainThreadLoop() + 491
4   browser_tests                       0x0000000112c8c847 ChromeBrowserMainParts::PreMainMessageLoopRunImpl() + 4375
5   browser_tests                       0x0000000112c8b62e ChromeBrowserMainParts::PreMainMessageLoopRun() + 62
6   browser_tests                       0x00000001116f2fa3 content::BrowserMainLoop::PreMainMessageLoopRun() + 67
7   browser_tests                       0x0000000111b07f57 content::StartupTaskRunner::RunAllTasksNow() + 39
8   browser_tests                       0x00000001116f16f8 content::BrowserMainLoop::CreateStartupTasks() + 712
9   browser_tests                       0x00000001116f54c0 content::BrowserMainRunnerImpl::Initialize(content::MainFunctionParams const&) + 96
10  browser_tests                       0x00000001116ef814 content::BrowserMain(content::MainFunctionParams const&) + 180
11  browser_tests                       0x0000000112abc0f2 content::ContentMainRunnerImpl::Run(bool) + 610
12  browser_tests                       0x0000000114ba7251 service_manager::Main(service_manager::MainParams const&) + 2849
13  browser_tests                       0x0000000112abb2e4 content::ContentMain(content::ContentMainParams const&) + 68
14  browser_tests                       0x00000001131cda19 content::BrowserTestBase::SetUp() + 2697
15  browser_tests                       0x0000000112c14d75 InProcessBrowserTest::SetUp() + 517
[21759:21515:0904/102202.805820:ERROR:browser_process_sub_thread.cc(210)] Waited 20 ms for network service
[21759:775:0904/102202.822748:WARNING:pref_notifier_impl.cc(23)] Pref observer found at shutdown.
[21759:775:0904/102202.822800:WARNING:pref_notifier_impl.cc(23)] Pref observer found at shutdown.
[  FAILED  ] ChromeNetworkServiceBrowserTest.EncryptedCookies, where TypeParam =  and GetParam() =  (1109 ms)

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/6e6fab4fea3dadde66ca075f2063989ebdcd67e1

commit 6e6fab4fea3dadde66ca075f2063989ebdcd67e1
Author: Robert Sesek <rsesek@chromium.org>
Date: Tue Sep 04 19:45:33 2018

Disable some failing network service tests on Mac-10.11.

https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Mac10.11%20Tests/28843

Tbr: jam@chromium.org
Bug: 868667, 880496
Change-Id: Ieaf46598dc1f2cbe384781b7510e51041ce62807
Reviewed-on: https://chromium-review.googlesource.com/1205013
Reviewed-by: Robert Sesek <rsesek@chromium.org>
Commit-Queue: Robert Sesek <rsesek@chromium.org>
Cr-Commit-Position: refs/heads/master@{#588620}
[modify] https://crrev.com/6e6fab4fea3dadde66ca075f2063989ebdcd67e1/chrome/browser/net/chrome_network_service_browsertest.cc
[modify] https://crrev.com/6e6fab4fea3dadde66ca075f2063989ebdcd67e1/chrome/browser/net/network_context_configuration_browsertest.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/93db813ea6170ae8a77b56287d4cdcd442e7969c

commit 93db813ea6170ae8a77b56287d4cdcd442e7969c
Author: Robert Sesek <rsesek@chromium.org>
Date: Wed Sep 05 22:29:40 2018

Reenable some network service tests on Mac, but not on Mac-10.11.

In 6e6fab4fea3dadde66ca075f2063989ebdcd67e1, these tests were disabled
on all of OS_MACOSX even though they were only failing on 10.11. Try to
reenable them on other macOS versions.

Bug: 868667, 880496
Change-Id: Icf41045f3fbe032ef06d995e02a0ad1b9f977c24
Reviewed-on: https://chromium-review.googlesource.com/1207611
Reviewed-by: John Abd-El-Malek <jam@chromium.org>
Commit-Queue: Robert Sesek <rsesek@chromium.org>
Cr-Commit-Position: refs/heads/master@{#589032}
[modify] https://crrev.com/93db813ea6170ae8a77b56287d4cdcd442e7969c/chrome/browser/net/chrome_network_service_browsertest.cc
[modify] https://crrev.com/93db813ea6170ae8a77b56287d4cdcd442e7969c/chrome/browser/net/network_context_configuration_browsertest.cc