Description

This fixes a bug where if we set one property on SettableMetadata (e.g. customMetadata), it would also set every other metadata property to null. This was stopping contentType from being inferred for android at least.

Unfortunately, the emulator doesn't infer contentType, so I tested on a live project and it is now inferring type if SettableMetadata is used without setting contentType.

Related Issues

fixes #12801

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