Tests affected
touch_GestureNav
touch_ScrollDirection
touch_TabSwitch
touch_TapSettings
touch_UpdateErrors.touchpad

Screenshot: https://screenshot.googleplex.com/OWSWy76z19A

This is not a flake, but consistent behavior for selected hosts. For several boards I observe only specific hosts are failing, e.g. sentry - 
https://screenshot.googleplex.com/A21YrqzTsv8 with this specific reason - https://screenshot.googleplex.com/p97yEWgUCNf

Action Items:

- Check if there is a bug in TP detection.
- If not luck, check on the specific host test beds.

The number of failing boards for the last month decreased - 7 boards -https://screenshot.googleplex.com/yiOy6bK543D

I'd explain this with DUT lab replacements. 
Will file bug for lab team to check on these 7 boards:
chromeos2-row4-rack8-host2		
chromeos4-row8-rack7-host16							
chromeos4-row8-rack9-host10						
chromeos4-row9-rack10-host19								
chromeos4-row12-rack8-host11	
chromeos6-row1-rack24-host15			
chromeos6-row2-rack15-host5

Filed b/120555273

I see at this point most boards miss touchpad input type in evtest output - https://paste.googleplex.com/6379642764132352

Like:
$ ssh root@chromeos4-row12-rack8-host11
localhost ~ # evtest
No device specified, trying to scan all of /dev/input/event*
Available devices:
/dev/input/event0:	Lid Switch
/dev/input/event1:	Power Button
/dev/input/event2:	Power Button
/dev/input/event3:	AT Translated Set 2 keyboard
/dev/input/event4:	HDA Intel PCH HDMI/DP,pcm=3
/dev/input/event5:	HDA Intel PCH HDMI/DP,pcm=7
/dev/input/event6:	HDA Intel PCH HDMI/DP,pcm=8
/dev/input/event7:	chtrt5650 Headset Jack
Select the device event number [0-7]: ^C
localhost ~ # 

One has it but might have been fixed already by lab team.

Most offending boards were having touchpad connection issues, and are fixed by lab team.

Now all boards have been fixed and the testare not failing with this reason.