Bug 735523 - Migrate sync_data from EBookBackendSqliteDB to EBookSqlite

We migrated the is_populated field, but not sync_data. EWS will need that.

(cherry picked from commit 52c1ab355f3d28bce8aed7259fa276665cd9bf0b)
Bug 735191 - [IMAPx] Avoid storing server-disallowed message flags