I tried to take dump on Samsung S6.
$dump
Following is the output I received (last line):
</hierarchy>sh: resetreason: can\'t execute: Permission denied\r\nKilled \r\n
Which permission is denied and who's getting killed?
It seems the output sent by the device contains those lines.
AndroidViewClient uses, by default and also depending on android version, uiautomator dump
to obtain the information it needs.
You can try
$ adb shell
$ uiautomator dump
to verify if the lines are there.