Reland 0c7d94eb: Add support for tar.gz archive files to download from download_from_google_storage

I fixed the overlapping argument and fixed up the tests so that the actual sha1 hash is now passed (since the tool actually check now that the downloaded file hash matches)

BUG=
R=hinoka@google.com

Review URL: https://codereview.chromium.org/1285423002 .

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@296346 0039d316-1c4b-4281-b951-d872f2087c98