As shown in the flakiness dashboard, a lot of these tests fail in a batch from time to time: https://test-results.appspot.com/dashboards/flakiness_dashboard.html#showAllRuns=true&testType=content_browsertests&tests=DumpAccessibilityTreeTest

A recent failure is https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Win10%20Tests%20x64%20%28dbg%29/2550

The logs just show that the general expectations weren't met, e.g.

[ RUN      ] DumpAccessibilityTreeTest.AccessibilityIframePostEnable
DevTools listening on ws://127.0.0.1:52897/devtools/browser/c265c67d-8b92-4741-894e-ea5d7aa5348e
[8940:4476:0817/053233.352:INFO:dump_accessibility_browsertest_base.cc(240)] Testing: C:/b/s/w/ir/content/test/data/accessibility/html/iframe.html
[8940:4476:0817/053233.352:INFO:dump_accessibility_browsertest_base.cc(242)] Expected output: C:/b/s/w/ir/content/test/data/accessibility/html/iframe-expected-blink.txt

or 

[ RUN      ] DumpAccessibilityTreeTest.AccessibilityAriaSortOnAriaGrid
DevTools listening on ws://127.0.0.1:52574/devtools/browser/0dd0db43-357d-4f5c-a0d0-84cfce3e1d49
[7964:7504:0817/051730.807:INFO:dump_accessibility_browsertest_base.cc(240)] Testing: C:/b/s/w/ir/content/test/data/accessibility/aria/aria-sort-aria-grid.html
[7964:7504:0817/051730.807:INFO:dump_accessibility_browsertest_base.cc(242)] Expected output: C:/b/s/w/ir/content/test/data/accessibility/aria/aria-sort-aria-grid-expected-blink.txt


dmazzoni@, nektar@, jamwalla@, aleventhal@: Can you please help investigate and find the right owner?