Idb82fe620c3395acaa8f051b4d4d0d770cd33d44 adds a unique contraints on
the revision id to export.xsd, which does not apply here
creating unique contraints in the same way than the pageids by adding an
offset
Change-Id: Ia19f1011a5c0ba8d21cc01a9be2e4d2ed300a80a
Follow up changes I84588e3d9692ee9eb7411b1e391abfc6c9ee89bf and
I030d245715174daeaf24723ebc156ab36761a035
Change-Id: I7e9d6d1e723af41b2af71f44e782f6d49b5f9909
From bug description: "This is helpful for incremental dumps, to know if
there are revisions missing between the last full dump and this
incremental dump"
Change-Id: I772f976942a306ad573efc659d09714e8250f5ec
backup_PageTest expect the ContentLanguage to be English
(backupTextPassTest and backup_LogTest also get the change,
but don't require it)
Change-Id: I8b3482df011bccd9fe520ba07c8b8d70de3b9dbb