deploy_chrome: punt dead GS constants
deploy_chrome: punt dead GS constants

This script uses the gs lib now for all of its needs, and these
google storage constants are now unused.  Punt them.

BUG=None
TEST=`scripts/deploy_chrome_unittest.py` passes

Change-Id: Iac33a73053d7e69c3456553e62b7db9d424f1009
Reviewed-on: https://gerrit.chromium.org/gerrit/41447
Reviewed-by: Ryan Cui <5ce1592d53754a87a44fc2eb7b63d5f77cf50fdb@chromium.org>
Commit-Queue: Mike Frysinger <8f3f75c74bd5184edcfa6534cab3c13a00a2f794@chromium.org>
Tested-by: Mike Frysinger <8f3f75c74bd5184edcfa6534cab3c13a00a2f794@chromium.org>

coreos/chromite,chadversary/chromiumos.chromite,bpsinc-native/src_third_party_chromite,chadversary/chromiumos.chromite,bpsinc-native/src_third_party_chromite,zhang0137/chromite,coreos/chromite,bpsinc-native/src_third_party_chromite,coreos/chromite,zhang0137/chromite,zhang0137/chromite