Code review comment for lp:~morphis/goget-ubuntu-touch/add-turbo-bootstrap-support

refer the conversation on irc, we might need to do some more operations to simulate fastboot -w then do update, so the proposed way might be 1. reboot recovery to erase data and cache partition 2. reboot recovery again to do update.

<ondra> alextu as for MP for recovery, so I still believe format cache is needed, but it should do proper cache format, or at least delete all from cache, not skip files under /cache/recovery
<ondra> alextu to fix cases when cache is running out of space and there are some old hanging files
<alextu> ondra, hmm ... agree, it seems no reason to keep updates which in /cache/recovery .
* alextu going to upload another mp for that.
<ondra> alextu problem is that then it's not gonna solve problem morphis|off is addressing with that change, when he wants to emulate fastboot -w
<ondra> alextu which should format userdata and cache
<ondra> alextu but then we wipe tarballs which we need to do install update, so it's kinda broken
<ondra> alextu only thing I can think of is to a) move format chache to the end, so it's formatted at the end of update, so it's safe to wipe it all, or we will need two runs, something like "format cache and userdata and reboot back to recovery" so u-d-f can start pushing files
<alextu> ondra, hmm ... sounds option b) is more like what we want to simulate
<ondra> alextu yep
<alextu> ondra, option a) will also remove cache/device-build which is the version of device tarball which updated by u-d-f
<ondra> alextu true