Fix flakiness caused by checking adb root status.

Remove the check from root_adb.
Add a retry for is_adb_root.

This was cherry picked from AOSP:
  https://android-review.googlesource.com/#/c/280495/

Bug=31803830
Test: $ python3 setup.py test; python setup.py test
      Ran ACTS on two test beds with two different devices in
      parallel, each test run finished correctly.

Change-Id: I6441e3bf3ad4bc794ff264718ac11b4156ff8b25
1 file changed
tree: 40cf2b749a66503bcd9658a045fbf846c9492d63
  1. acts/
  2. Android.mk