Nexus5X was missing int storage map association between bot names and bisect bot names. I added it to the config and it is now displayed in the dropdown.

Please note: Although Nexus5x bisect bot is displayed in the dropdownlist, this is not selected as default when we want to run bisect on nexus5x perf regression.  I'll discuss with qyearsley, about the possible to fix for this.

Meanwhile please select Nexus5x manually from the dashboard.

Here is the Job I kicked out via dashboard
https://build.chromium.org/p/tryserver.chromium.perf/builders/android_nexus5X_perf_bisect/builds/12

We found what appears to be the cause for this; fix in https://codereview.chromium.org/1806333007

I'm pretty sure we verified this as fixed now.