The test is flaking with mash on the fyi bot. For example, https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Mojo%20ChromiumOS/38872

[ RUN      ] PDFAnnotationsTest.AnnotationsFeatureEnabled
[1:1:0104/111101.894219:INFO:hugepage_text.cc(68)] Mlocking text pages failed: Cannot allocate memory (12)
[24317:24317:0104/111101.963758:WARNING:chrome_browser_main_chromeos.cc(544)] Running as stub user with profile dir: test-user
[ash:24429:24429:0104/111102.250418:ERROR:layer_tree_host_impl.cc(3122)] Forcing zero-copy tile initialization as worker context is missing
[ash:24429:24429:0104/111102.272758:ERROR:layer_tree_host_impl.cc(3122)] Forcing zero-copy tile initialization as worker context is missing
[24317:24317:0104/111102.319917:WARNING:easy_unlock_service_regular.cc(438)] EasyUnlockServiceRegular::IsInLegacyHostMode: DeviceSyncClient not ready. Returning false.
[24317:24317:0104/111102.369365:INFO:remote_commands_service.cc(38)] Fetching remote commands.
[24317:24317:0104/111102.369703:WARNING:remote_commands_service.cc(40)] Client is not registered.
[24317:24317:0104/111102.369773:INFO:remote_commands_invalidator.cc(32)] Initialize RemoteCommandsInvalidator.
[24317:24317:0104/111102.369811:INFO:remote_commands_invalidator.cc(57)] Starting RemoteCommandsInvalidator.
[24317:24317:0104/111102.369849:INFO:remote_commands_invalidator.cc(123)] RemoteCommandsInvalidator ReloadPolicyData.
[24317:24317:0104/111102.369884:INFO:remote_commands_invalidator.cc(167)] Unregister RemoteCommandsInvalidator.
[24317:24317:0104/111102.416354:WARNING:wallpaper_controller_client.cc(358)] Cannot get wallpaper files id in RemovePolicyWallpaper. This should never happen under normal circumstances.
[ash:24429:24429:0104/111102.443381:ERROR:shell_delegate_mash.cc(51)] Not implemented reached in virtual bool ash::ShellDelegateMash::CanShowWindowForUser(aura::Window *) const
[24317:24317:0104/111102.618748:WARNING:personal_data_manager.cc(483)] 0xa5007600a00 refresh is done, notifying PersonalDataChanged
[24317:24317:0104/111102.619460:WARNING:personal_data_manager.cc(483)] 0xa5007601b80 refresh is done, notifying PersonalDataChanged
[24317:24317:0104/111102.636043:ERROR:remote_text_input_client.cc(144)] Not implemented reached in virtual void RemoteTextInputClient::OnInputMethodChanged()
[24317:24317:0104/111102.636086:ERROR:remote_text_input_client.cc(101)] Not implemented reached in virtual ui::TextInputClient::FocusReason RemoteTextInputClient::GetFocusReason() const
[24317:24317:0104/111102.636094:ERROR:remote_text_input_client.cc(185)] Not implemented reached in virtual bool RemoteTextInputClient::ShouldDoLearning()
[24317:24317:0104/111102.636124:ERROR:remote_text_input_client.cc(95)] Not implemented reached in virtual bool RemoteTextInputClient::HasCompositionText() const
[24317:24317:0104/111102.636131:ERROR:remote_text_input_client.cc(107)] Not implemented reached in virtual bool RemoteTextInputClient::GetTextRange(gfx::Range *) const
[1:8:0104/111102.792647:ERROR:layer_tree_host_impl.cc(3122)] Forcing zero-copy tile initialization as worker context is missing
[1:8:0104/111102.797175:ERROR:layer_tree_host_impl.cc(3122)] Forcing zero-copy tile initialization as worker context is missing
[24317:24317:0104/111102.814797:ERROR:render_widget_host_view_aura.cc(1300)] Not implemented reached in virtual base::i18n::TextDirection content::RenderWidgetHostViewAura::GetTextDirection() const
[24317:24553:0104/111102.884687:WARNING:embedded_test_server.cc(237)] Request not handled. Returning 404: /favicon.ico
[1:8:0104/111103.081159:ERROR:layer_tree_host_impl.cc(3122)] Forcing zero-copy tile initialization as worker context is missing
[24317:24317:0104/111103.085715:INFO:CONSOLE(0)] "HTML Imports is deprecated and will be removed in M73, around March 2019. Please use ES modules instead. See https://www.chromestatus.com/features/5144752345317376 for more details.", source:  (0)
[24317:24317:0104/111103.491206:INFO:CONSOLE(442)] "document.registerElement is deprecated and will be removed in M73, around March 2019. Please use window.customElements.define instead. See https://www.chromestatus.com/features/4642138092470272 for more details.", source: chrome://resources/polymer/v1_0/polymer/polymer-micro-extracted.js (442)
[24317:24317:0104/111104.000761:INFO:CONSOLE(2083)] "Element.createShadowRoot is deprecated and will be removed in M73, around March 2019. Please use Element.attachShadow instead. See https://www.chromestatus.com/features/4507242028072960 for more details.", source: chrome://resources/polymer/v1_0/polymer/polymer-mini-extracted.js (2083)
[1:8:0104/111104.297678:ERROR:layer_tree_host_impl.cc(3122)] Forcing zero-copy tile initialization as worker context is missing
[1:1:0104/111104.628188:WARNING:resource_message_handler.cc(49)] 'Post' message handler failed to complete successfully.
[24317:24317:0104/111104.680122:INFO:CONSOLE(0)] "[SUCCESS] testAnnotationsEnabled", source: chrome-extension://mhjfbmdgcfjbbpaeojofohoefgiehjai/index.html (0)
[1:1:0104/111104.834706:WARNING:resource_message_handler.cc(49)] 'Post' message handler failed to complete successfully.
[24317:24317:0104/111104.854964:INFO:CONSOLE(0)] "[SUCCESS] testEnterAndExitAnnotationMode", source: chrome-extension://mhjfbmdgcfjbbpaeojofohoefgiehjai/index.html (0)
[24317:24317:0104/111104.931394:INFO:CONSOLE(0)] "[FAIL] testViewportToCameraConversion: API Test Error in testViewportToCameraConversion
Actual: -423.75
Expected: -442.5
Error
    at extensions::test:243:18
    at testAsync (<anonymous>:665:21)", source: chrome-extension://mhjfbmdgcfjbbpaeojofohoefgiehjai/index.html (0)
[24317:24317:0104/111104.931565:INFO:CONSOLE(0)] "[FAIL] testViewportToCameraConversion: chrome.test.failure
Error
    at testAsync (<anonymous>:608:17)", source: chrome-extension://mhjfbmdgcfjbbpaeojofohoefgiehjai/index.html (0)
[24317:24317:0104/111104.937675:INFO:CONSOLE(610)] "Uncaught (in promise) chrome.test.failure", source: chrome-extension://mhjfbmdgcfjbbpaeojofohoefgiehjai/index.html (610)
../../chrome/browser/pdf/pdf_extension_test.cc:199: Failure
Failed
Failed 2 of 3 tests
Stack trace:
#0 0x55cd41a8a81c testing::internal::UnitTestImpl::CurrentOsStackTraceExceptTop()
#1 0x55cd41a8a209 testing::internal::AssertHelper::operator=()
#2 0x55cd403257fc PDFExtensionTest::RunTestsInFile()
#3 0x55cd40326931 PDFAnnotationsTest_AnnotationsFeatureEnabled_Test::RunTestOnMainThread()
#4 0x55cd450424fa content::BrowserTestBase::ProxyRunTestOnMainThreadLoop()
#5 0x55cd44adaad6 ChromeBrowserMainParts::PreMainMessageLoopRunImpl()
#6 0x55cd44ad98a8 ChromeBrowserMainParts::PreMainMessageLoopRun()
#7 0x55cd415111d0 chromeos::ChromeBrowserMainPartsChromeos::PreMainMessageLoopRun()
#8 0x55cd42a5be42 content::BrowserMainLoop::PreMainMessageLoopRun()
#9 0x55cd42f14575 content::StartupTaskRunner::RunAllTasksNow()
#10 0x55cd42a5ab25 content::BrowserMainLoop::CreateStartupTasks()
#11 0x55cd42a5dfe4 content::BrowserMainRunnerImpl::Initialize()
#12 0x55cd42a58b47 content::BrowserMain()
#13 0x55cd445c039c content::ContentMainRunnerImpl::RunServiceManager()
#14 0x55cd445bffa1 content::ContentMainRunnerImpl::Run()
#15 0x55cd46c74ff3 service_manager::Main()
#16 0x55cd445be5d4 content::ContentMain()
#17 0x55cd45041fe2 content::BrowserTestBase::SetUp()
#18 0x55cd44a7eb33 InProcessBrowserTest::SetUp()

[24317:24317:0104/111105.062962:WARNING:render_widget_host_impl.cc(275)] Input request on unbound interface
[24317:24317:0104/111105.062993:WARNING:render_widget_host_impl.cc(275)] Input request on unbound interface
[ash:24429:24449:0104/111105.087655:WARNING:ipc_message_attachment_set.cc(49)] MessageAttachmentSet destroyed with unconsumed attachments: 0/1
[24317:24317:0104/111105.136712:ERROR:http_bridge.cc(126)] Not implemented reached in virtual void syncer::HttpBridgeFactory::OnSignalReceived()
[24317:24317:0104/111105.138340:INFO:remote_commands_invalidator.cc(45)] Shutdown RemoteCommandsInvalidator.
[24317:24317:0104/111105.138401:INFO:remote_commands_invalidator.cc(68)] Stopping RemoteCommandsInvalidator.
[24317:24317:0104/111105.138415:INFO:remote_commands_invalidator.cc(167)] Unregister RemoteCommandsInvalidator.
[24317:24317:0104/111105.170473:WARNING:pref_notifier_impl.cc(23)] Pref observer found at shutdown.
[24317:24317:0104/111105.170524:WARNING:pref_notifier_impl.cc(23)] Pref observer found at shutdown.
[  FAILED  ] PDFAnnotationsTest.AnnotationsFeatureEnabled, where TypeParam =  and GetParam() =  (3476 ms)