Add JsonContent.Create overloads which accept JsonTypeInfo

[brantburnett]

This adds JsonContent.Create overloads that accept JsonTypeInfo parameters as approved in #51544.

namespace System.Net.Http.Json
{
    public partial class JsonContent
    {
        public static JsonContent Create<TValue>(TValue? inputValue, JsonTypeInfo<TValue> jsonTypeInfo, MediaTypeHeaderValue? mediaType = null);
        public static JsonContent Create(object? inputValue, JsonTypeInfo jsonTypeInfo, MediaTypeHeaderValue? mediaType = null);
    }
}

I did consider changing the internal JsonContent<T> overload to inherit from JsonContent. However, this requires unsealing JsonContent which was not approved. More importantly, to work well ObjectType and especially Value would need to be made virtual, which is not an allowed change to the API surface due to binary compatibility requirements. This approach seemed cleaner at the cost of a very lightweight additional abstraction layer.

Fixes #51544

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Issue Details

---

This adds JsonContent.Create overloads that accept JsonTypeInfo parameters as approved in #51544.

namespace System.Net.Http.Json
{
    public partial class JsonContent
    {
        public static JsonContent Create<TValue>(TValue? inputValue, JsonTypeInfo<TValue> jsonTypeInfo, MediaTypeHeaderValue? mediaType = null);
        public static JsonContent Create(object? inputValue, JsonTypeInfo jsonTypeInfo, MediaTypeHeaderValue? mediaType = null);
    }
}

I did consider changing the internal JsonContent<T> overload to inherit from JsonContent. However, this requires unsealing JsonContent which was not approved. More importantly, to work well ObjectType and especially Value would need to be made virtual, which is not an allowed change to the API surface due to binary compatibility requirements. This approach seemed cleaner at the cost of a very lightweight additional abstraction layer.

Fixes #51544

Author:	brantburnett
Assignees:	-
Labels:	area-System.Text.Json, new-api-needs-documentation
Milestone:	-

[eiriktsarpalis]

Thank you for your contribution, and for simplifying the implementation :-)

[brantburnett]

Thank you for your contribution, and for simplifying the implementation :-)

Thanks for teaching me the new JsonTypeInfo tricks. :)