Bug 2073610 - [AS] Update SyncParams to allow omitting engine enabl…

[bytesized]

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[mhammond]

I don't really understand this - is there ever a time when we'd want to treat None and an empty map as different? What does this enable?

[lougeniaC64]

I don't really understand this - is there ever a time when we'd want to treat None and an empty map as different? What does this enable?

@mhammond Are you saying that setting enabled_changes to optional is not necessary for per-device syncing, or that there are implementation details you'd like changed? I thought passing None instead of an empty map might be useful for distinguishing between a legacy sync with no enabled changes and a per-device sync. I created this ticket based on a discussion we had in early August but if there isn't an issue with PDS passing an empty map for enabled_changes this work isn't necessary. cc @bytesized