[chromedriver] Archive all builds that pass the tests. Simplify release code.

gs://chromedriver contains just releases and is permanent.
gs://chromedriver-data is configured to delete objects older than 50 days.
All releases goto gs://chromedriver, and prebuilts, archives, and test results go into gs://chromedriver-data
BUG=none
NOTRY=true
R=craigdh@chromium.org

Review URL: https://codereview.chromium.org/24693002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@225530 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 225530