Suppress some (fatal) warnings in schemas.

[robertwb]

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[robertwb]

@kennknowles Ping? Was this subsumed by another PR?

[kennknowles]

Yea, this looks good. I hadn't had a chance to see what was suppressed. There's definitely a world in which we have the same functionality with no warnings and no suppressions, so I wanted to get that recorded in the cleanup JIRAs.

[robertwb]

Thanks.