autotest: Remove autox code and tests that use it

BUG=chromium:368932
TEST=build for daisy, lumpy, x86-alex

CQ-DEPEND=CL:199090

Change-Id: I3966fb1040e634cfe22397c7cfa06fb482feb413
Reviewed-on: https://chromium-review.googlesource.com/199053
Tested-by: Gaurav Shah <gauravsh@chromium.org>
Reviewed-by: Yusuke Sato <yusukes@chromium.org>
Reviewed-by: Gaurav Shah <gauravsh@chromium.org>
Commit-Queue: Gaurav Shah <gauravsh@chromium.org>
8 files changed