More tests needed

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The com.google.gwt project may have more tests that can be migrated. Additionally, recent changes have found a few bugs that should be tested in the library (not in downstream apps):

• enums
• arrays of arrays
• arrays of primitives
• concurrency on either client or server implementations
• verifying error messages for expected-but-missing field access

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• subclasses/superclasses with/without fields
• Generics on non-custom field serializer types (for types that do require custom field serializer, see Set, ArrayList, Map break deserialization #12)

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• Generics used in fields/properties of objects with generated serializers (Generics break serialization #16)

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• Enum with no values