I've seen couple of tests in the suite fail:
PluginPowerSaverBrowserTest.SmallerThanPlayIcon
PluginPowerSaverBrowserTest.PosterTests
They both time out on PluginPowerSaverBrowserTest::VerifySnapshot()

Builds:
https://build.chromium.org/p/chromium.linux/builders/Linux%20Tests/builds/45541
https://build.chromium.org/p/chromium.linux/builders/Linux%20Tests/builds/45542
https://build.chromium.org/p/chromium.linux/builders/Linux%20Tests/builds/45544


Sample logs:
[ RUN      ] PluginPowerSaverBrowserTest.PosterTests
Xlib:  extension "RANDR" missing on display ":9".
Xlib:  extension "RANDR" missing on display ":9".
[21291:21291:0829/102739:WARNING:audio_manager.cc(317)] Multiple instances of AudioManager detected
[21291:21291:0829/102739:WARNING:audio_manager.cc(278)] Multiple instances of AudioManager detected
[21291:21291:0829/102739:WARNING:password_store_factory.cc(248)] Using basic (unencrypted) store for password storage. See https://chromium.googlesource.com/chromium/src/+/master/docs/linux_password_storage.md for more information about password storage options.
BrowserTestBase received signal: Terminated. Backtrace:
#0 0x0000024dea2e base::debug::StackTrace::StackTrace()
#1 0x0000029ed499 content::(anonymous namespace)::DumpStackTraceSignalHandler()
#2 0x7faa6d24f0b0 <unknown>
#3 0x7faa6d300993 __poll
#4 0x7faa72776ff6 <unknown>
#5 0x7faa72777124 g_main_context_iteration
#6 0x0000024f6526 base::MessagePumpGlib::Run()
#7 0x00000250ceae base::RunLoop::Run()
#8 0x000002a129fc content::RunThisRunLoop()
#9 0x000002a1299a content::RunMessageLoop()
#10 0x000000c557a3 PluginPowerSaverBrowserTest::VerifySnapshot()
#11 0x000000c5616c PluginPowerSaverBrowserTest_PosterTests_Test::RunTestOnMainThread()
#12 0x00000256e0ff InProcessBrowserTest::RunTestOnMainThreadLoop()
#13 0x0000029ed209 content::BrowserTestBase::ProxyRunTestOnMainThreadLoop()
#14 0x0000028796a0 ChromeBrowserMainParts::PreMainMessageLoopRunImpl()
#15 0x0000028786b5 ChromeBrowserMainParts::PreMainMessageLoopRun()
#16 0x000001d37665 content::BrowserMainLoop::PreMainMessageLoopRun()
#17 0x000001fd0327 content::StartupTaskRunner::RunAllTasksNow()
#18 0x000001d35b84 content::BrowserMainLoop::CreateStartupTasks()
#19 0x000001d3a5fd content::BrowserMainRunnerImpl::Initialize()
#20 0x000001d32f38 content::BrowserMain()
#21 0x0000024c5837 content::ContentMainRunnerImpl::Run()
#22 0x0000024c4320 content::ContentMain()
#23 0x0000029ecbe1 content::BrowserTestBase::SetUp()
#24 0x00000256c9e4 InProcessBrowserTest::SetUp()
#25 0x000002ed74b8 testing::Test::Run()
#26 0x000002ed8223 testing::TestInfo::Run()
#27 0x000002ed86b7 testing::TestCase::Run()
#28 0x000002edf6e7 testing::internal::UnitTestImpl::RunAllTests()
#29 0x000002edf33a testing::UnitTest::Run()
#30 0x000002578273 base::TestSuite::Run()
#31 0x0000024d3819 ChromeTestSuiteRunner::RunTestSuite()
#32 0x000002a0f8ef content::LaunchTests()
#33 0x0000024d1da1 main
#34 0x7faa6d23a7ed __libc_start_main
#35 0x0000005c7bad <unknown>
[1047/1047] PluginPowerSaverBrowserTest.PosterTests (TIMED OUT)