[2.10.x] make ImmutableLinkedHashMap serializable

[ramazanyich]

Pull Request Checklist

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• Have you squashed your commits?
• Have you added copyright headers to new files?
• Have you updated the documentation?
• Have you added tests for any changed functionality?

Fixes

Fixes #944

Purpose

In order to be able to serialize objects that contain JsObject as a member need to have internal underlying ImmutableLinkedHashMap implement serializable interface

[ramazanyich]

have you an idea how I can test the serialization in scala-native.
Looks like problem is in fact that ObectInputStream/ObjectOutputStream is not included into javalibs of scala-native.
which gives a problem during test/NativeLink

[jtjeferreira]

have you an idea how I can test the serialization in scala-native. Looks like problem is in fact that ObectInputStream/ObjectOutputStream is not included into javalibs of scala-native. which gives a problem during test/NativeLink

I think it is better to just have that test as JVM test in play-json/jvm/src/test/scala/play/api/libs/json

[ramazanyich]

have you an idea how I can test the serialization in scala-native. Looks like problem is in fact that ObectInputStream/ObjectOutputStream is not included into javalibs of scala-native. which gives a problem during test/NativeLink

I think it is better to just have that test as JVM test in play-json/jvm/src/test/scala/play/api/libs/json

thanks for the tip

[jtjeferreira]

LGTM, but would be better if a maintainer could have a look

[ramazanyich]

@mkurz can you take a look on this PR

[mkurz]

Should work

[mkurz]

@Mergifyio backport main

[mergify]

backport main

✅ Backports have been created

• #948 [main] make ImmutableLinkedHashMap serializable (backport #945) by @ramazanyich has been created for branch main