Modifies dev server to produce stateful gzip and modify image_to_live to use it.

Modifies dev server to produce stateful gzip and modify image_to_live to use it.

TEST=Tested with image_to_live, memento_updater without image_to_live

This mimics the update process of the real image for the stateful partition.
By moving this the update into a separate script, I can add it to the gmerge
package such that developers will not have to use image_to_live.  This change
also removes the dependency on tar.

[sosa, 2010-04-30 23:46:36]

Kmixter for script + image_to_live, seano for devserver changes

[sosa, 2010-04-30 23:49:36]

+sleffler

Will be adding stateful_update.sh to the gmerge package.  This way to update
from a device (without having to have ssh connection), you just need to do:

sudo /opt/google/memento_updater.sh
sudo stateful_update.sh
sudo reboot

[seano, 2010-05-03 23:07:16]

Nice cleanup. lgtm++

http://codereview.chromium.org/1774021/diff/4001/5001
File src/platform/dev/autoupdate.py (right):

http://codereview.chromium.org/1774021/diff/4001/5001#newcode87
src/platform/dev/autoupdate.py:87: for i in range(0, 4):
Random nit: range(4) is fine..

http://codereview.chromium.org/1774021/diff/4001/5001#newcode125
src/platform/dev/autoupdate.py:125: web.debug('unzip image.zip failed.')
Did you test this out in -a mode? (e.g. serving buildbot-style image.zip dirs?)

http://codereview.chromium.org/1774021/diff/4001/5002
File src/platform/dev/stateful_update.sh (right):

http://codereview.chromium.org/1774021/diff/4001/5002#newcode23
src/platform/dev/stateful_update.sh:23: STATEFUL_UPDATE_URL="`dirname
\"$ROOT_UPDATE_URL\"`/stateful.image.gz"
use $(cmd) to get subshell output

http://codereview.chromium.org/1774021/diff/4001/5002#newcode39
src/platform/dev/stateful_update.sh:39: gzip -d "$STATEFUL_UPDATE"
You could wget to stdout and pipe it here, and forget about creating the
intermediate file. It doesn't look like you reuse it anywhere else, except to
clean it up again below.