Struct parsing is flaky if unions are part of struct

[gricha]

Currently struct parsing will be flaky if unions are part of struct. The reason for that is that we don't try to match against ?(..content..), and that's how unions are encoded by iOS.

[sunbohong]

I have the same problem. Does the Facebook maintenance team have a plan to fix it?

[gricha]

I'll defer to Facebook folks.