On the Win7 dbg bot, the test often flakes with the following message:

[ RUN      ] BrowserCloseManagerBrowserTest/BrowserCloseManagerBrowserTest.TestAddWindowDuringShutdown/1
[4088:5592:0801/050135.047:WARNING:chrome_browser_main_win.cc(483)] Command line too long for RegisterApplicationRestart:  --brave-new-test-launcher --cfi-diag=0 --gtest_also_run_disabled_tests --gtest_filter=BrowserCloseManagerBrowserTest/BrowserCloseManagerBrowserTest.TestAddWindowDuringShutdown/1 --single_process --test-launcher-bot-mode --test-launcher-summary-output="e:\b\swarm_slave\w\io71xzla\output.json" --user-data-dir="C:\Users\CHROME~2\AppData\Local\Temp\scoped_dir3740_20873\d3740_20404" --disable-offline-auto-reload --enable-fast-unload --no-first-run --no-default-browser-check --enable-logging=stderr --safebrowsing-disable-auto-update --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=45 --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-features=NetworkPrediction --flag-switches-begin --flag-switches-end --restore-last-session about:blank
[692:5260:0801/050135.495:ERROR:direct_composition_surface_win.cc(1073)] Failing to detect HDR, couldn't retrieve D3D11 device from ANGLE.
[692:5260:0801/050135.526:INFO:media_foundation_video_encode_accelerator_win.cc(335)] Windows versions earlier than 8 are not supported.
[4088:1936:0801/050136.865:WARNING:embedded_test_server.cc(219)] Request not handled. Returning 404: /favicon.ico
[2076:5044:0801/050138.319:ERROR:render_process_impl.cc(176)] WebFrame LEAKED 1 TIMES

See https://uberchromegw.corp.google.com/i/chromium.win/builders/Win7%20Tests%20%28dbg%29%281%29?numbuilds=25 or https://uberchromegw.corp.google.com/i/chromium.win/builders/Win7%20Tests%20%28dbg%29%281%29/builds/61992 in particular.