Failures all seem to be because two InputDeviceManagers are getting created. Here's sample output:

[ RUN      ] SBER/PasswordProtectionServiceTest.TestSyncPasswordEntryRequestAndResponseSuccessfull/0
[10894:10894:1217/101627.308308:13364149023:FATAL:input_device_manager.cc(16)] Check failed: g_instance. InputDeviceManager::SetInstance must be called before getting the instance of InputDeviceManager.
#0 0x56159f675e4f base::debug::StackTrace::StackTrace()
#1 0x56159f5dda5b logging::LogMessage::~LogMessage()
#2 0x5615a048b7dd ui::InputDeviceManager::GetInstance()
#3 0x56159eca813c content::InputDeviceChangeObserver::InputDeviceChangeObserver()
#4 0x56159ed1f397 content::RenderViewHostImpl::RenderViewHostImpl()
#5 0x56159ed1e885 content::RenderViewHostFactory::Create()
#6 0x56159eb08878 content::FrameTree::CreateRenderViewHost()
#7 0x56159eb63c9f content::RenderFrameHostManager::CreateRenderFrameHost()
#8 0x56159eb63b69 content::RenderFrameHostManager::Init()
#9 0x56159ee4264e content::WebContentsImpl::Init()
#10 0x5615a1212161 content::TestWebContents::Create()
#11 0x56159d0bdb70 safe_browsing::PasswordProtectionServiceTest_TestSyncPasswordEntryRequestAndResponseSuccessfull_Test::TestBody()
#12 0x56159d2ca961 testing::Test::Run()
#13 0x56159d2cb4cf testing::TestInfo::Run()
#14 0x56159d2cb9f7 testing::TestCase::Run()
#15 0x56159d2d7c37 testing::internal::UnitTestImpl::RunAllTests()
#16 0x56159d2d77ad testing::UnitTest::Run()
#17 0x5615a0356821 base::TestSuite::Run()
#18 0x5615a035906d base::(anonymous namespace)::LaunchUnitTestsInternal()
#19 0x5615a0358ed1 base::LaunchUnitTests()
#20 0x56159cac402d main
#21 0x7f40aa463f45 __libc_start_main
#22 0x56159b49690a _start

You can see this if you change the default for the SingleProcessMash feature flag to ENABLED_BY_DEFAULT.