This reverts commits:
  dbbf350a Fix trailing whitespace test.
  b4f1d449 Fix actual pylint errors.
  0d9ecc92 Reland "gclient eval: Expand vars while parsing DEPS files"

Reason: http://crbug.com/825724 Clank Official Build Failure - 65.0.3325.193

TBR=agable@chromium.org

Bug: 825724
Change-Id: Icef2d0ccc8a13b782a8e3d6b474b1281820947b5
Reviewed-on: https://chromium-review.googlesource.com/980334
Commit-Queue: Edward Lesmes <ehmaldonado@chromium.org>
Reviewed-by: Edward Lesmes <ehmaldonado@chromium.org>