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Bug 853388: Upgrade existing SQLITE databases to JSON; r=unfocused
Bug 853388: Remove transaction model of database flush control and implement async save of database; r=unfocused
Bug 853388: Trigger XPI database conversion from SQLITE based on schema version preference; r=unfocused
Bug 853388: Load JSON database asynchronously outside of startup; r=unfocused
Bug 853388: Keep trying to save JSON even if read or save fails; r=unfocused