Revert "[autotest] Threaded asynchronous task execution on drones." 

Problems with the retry decorator and localhost threads.

This reverts commit 0933899b0dd1320e90e06025cced8096aed44908.

Change-Id: I99318b4bdf4c11e9c4e5181c4ff5b1bdcdcbb89c
Reviewed-on: https://chromium-review.googlesource.com/207038
Reviewed-by: Prashanth B <beeps@chromium.org>
Commit-Queue: Prashanth B <beeps@chromium.org>
Tested-by: Prashanth B <beeps@chromium.org>
9 files changed