Fix support for non-public default constructors using JsonIncludeAttribute

[eiriktsarpalis]

PR #88452 added support for non-public constructors using JsonIncludeAttribute, however it didn't account for default constructors, which use a different path when being populated in the reflection serializer.

Fix #90577

Should be backported to release/8.0-rc1

[eiriktsarpalis]

/backport to release/8.0-rc1

[github-actions]

Started backporting to release/8.0-rc1: https://github.com/dotnet/runtime/actions/runs/5869872173

[ghost]

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Issue Details

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PR #88452 added support for non-public constructors using JsonIncludeAttribute, however it didn't account for default constructors, which use a different path when being populated in the reflection serializer.

Fix #90577

Should be backported to release/8.0-rc1

Author:	eiriktsarpalis
Assignees:	eiriktsarpalis
Labels:	area-System.Text.Json
Milestone:	8.0.0

[tarekgh]

LGTM!

[TanvirArjel]

@eiriktsarpalis Title looks misleading. It should be "Fix support for non-public default constructors using JsonConstructorAttribute " isn't it? Please confirm you have made the fix for JsonConstructorAttribute, not JsonIncludeAttribute!

[eiriktsarpalis]

Yes that's a typo, it is in fact addressing the issue with JsonConstructorAttribute. PR has been merged now, so not much can be done. 🤷