Serialization should be done the same way for all types

[vaadin-bot]

Originally by @Artur-

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Currently serialization/deserialization code is generated on the client side for SharedState types and types they refer to. Some types like Map, List, arrays are handled in other parts of the framework. It would be much clearer if all types were handled in the same way i.e. one serializer class per type. There is no need to generate the serializers for standard types but they should implement the same interface as the generated serializers.

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Imported from https://dev.vaadin.com/ issue #8449

[stale[bot]]

Hello there!

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