Remove message and domain from logbook state_changed events

[bdraco]

The changes have been merged into frontend 20200930.0. This can merge once frontend if bumped in core.

Breaking change

Remove message and domain from logbook state_changed events

These are now handled by the frontend as we move closer
to making the logbook localized.

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[bdraco]

This can merge as soon as frontend is bumped

[bdraco]

Verified working as expected with #40794