[Merge] ~mwhudson/livecd-rootfs/+git/livecd-rootfs:tpm-seed-in-live-layer into livecd-rootfs:ubuntu/master

[Łukasz Zemczak]

Review: Needs Information

Ok, I don't think I understand how this will work and how it will save space. I need someone to give me some context.
Right now we specifically used the uc20 system seed in the enhanced-secureboot layer because this is the layer that gets copied over to the target system. Now we're moving it to the live layer (which is NOT going to be installed), so I assume snapd is doing some preseeding itself during installation that we don't actually need to copy over a seeded state? Is that the case?

But then still, how is this saving space? The live layer didn't have any snaps, but now we basically moved what was in the enhanced-secureboot layer to the live layer. So the iso, per my limited understanding, should have the same size as it had before since nothing changed? What is the logic behind the shrinking of the iso?

Need context!
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https://code.launchpad.net/~mwhudson/livecd-rootfs/+git/livecd-rootfs/+merge/466202
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