Add temporary solution to avoid a panic

[nathanielc]

This is a temporary fix to avoid the panic caused in #367 and #357

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[nathanielc]

I signed it!

[googlebot]

CLAs look good, thanks!

[sdboyer]

thanks for doing this - just a little nit 😄

[sdboyer]

nit: let's use the two-return form of map lookups here, and check against that for this ase, rather than checking if fromErr == nil.

[sdboyer]

thanks! 🎉