autoupdate_EndToEnd: Fix a bunch of pylint errors.

This is mostly about bad indentation, documentation, and proper method
declaration.  There are also some minor structural code changes for
better readability and/or reusability.

BUG=None
TEST=pylint

Change-Id: I0205b58b838545b1c93a68dc8cda87948d3bec49
Reviewed-on: https://chromium-review.googlesource.com/184649
Tested-by: Gilad Arnold <garnold@chromium.org>
Reviewed-by: Don Garrett <dgarrett@chromium.org>
Commit-Queue: Gilad Arnold <garnold@chromium.org>
1 file changed