[Inconsistent message] Adapt CS0236 message text to post C# 12.0

[zorgoz]

The message currently looks like CS0236 A field initializer cannot reference the non-static field, method, or property ....
However, this is not true anymore:

Value is indeed a non-static member, that might or might not be initialized at that point.

public class X1
{ 
	public int Value { get; }
	public int DoubleValue { get; set; } = Value*2; // << CS0236 on Value
	
	public X1(int value)
	{
		Value = value;
	}
}

However, in the following scenario, there is no error, as the primary constructor will initialize Value ahead of that statement.
But, the message does not include this scenario as an exception to the rule.

public class X2(int Value)
{
	public int DoubleValue { get; set; } = Value * 2;
}

[jnm2]

A primary parameter is none of the things mentioned in the error message, so the error message is accurate. The error message doesn't list things that are valid; that would be a very long list.

[zorgoz]

The parameter is not, but the backing filed referenced by the expression is a non-static field. Unless it is using the parameter directly and not the backing field.

[HaloFour]

Correct, it is using the parameter directly. Also, since the parameter is not used again post-construction, no field is emitted for it.

[jnm2]

@zorgoz Even if there is a backing field in the lowering strategy, that would not matter from the lens of the language itself. It would be mixing abstraction layers, so to speak.

[TahirAhmadov]

#6128