This bot went purple briefly on 3 Dec, but it came back in the next build, but it stopped reporting memory:chrome:all_processes:reported_by_chrome:cc:effective_size_avg/background for all of the pages at some point while it was purple.
The dashboard links to the revision range in the next build (when the bot went purple) but that's useless because the bot failed due to gsutil, not chrome.
https://build.chromium.org/p/chromium.perf/builders/Android%20One%20Perf%20%283%29/builds/4454
The next build shows the benchmark green again, Logdog says PASSED:
https://luci-logdog.appspot.com/v/?s=chrome%2Fbb%2Fchromium.perf%2FAndroid_One_Perf__3_%2F4455%2F%2B%2Frecipes%2Fsteps%2Fmemory.top_10_mobile_stress%2F0%2Fstdout
But the background version of this metric is missing from the chart-json
https://luci-logdog.appspot.com/v/?s=chrome%2Fbb%2Fchromium.perf%2FAndroid_One_Perf__3_%2F4455%2F%2B%2Frecipes%2Fsteps%2Fmemory.top_10_mobile_stress%2F0%2Flogs%2Fjson.output%2F0

Not sure what the next step is?