Add --official_build to archive_build for official builds.
Add --official_build to archive_build for official builds.

BUG=chromium-os:15335
TEST=unittests, pyflakes on cbuildbot_commands and
--dump_config on x86-mario-private-full to verify chromeos-official
was set correctly

Change-Id: I3d5b7b6b15e5b9bee8cca66c925c7ff93c19feb1
Reviewed-on: http://gerrit.chromium.org/gerrit/1134
Tested-by: Chris Sosa <959d3d631fb6f17f1b07f751372041a1edb210d1@chromium.org>
Reviewed-by: Chris Sosa <959d3d631fb6f17f1b07f751372041a1edb210d1@chromium.org>

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