Fix IDesignerSerializationManager nullability

[elachlan]

The documentation states that many of the functions can return null. So I have updated the nullability based on the documentation.

https://learn.microsoft.com/en-us/dotnet/api/system.componentmodel.design.serialization.idesignerserializationmanager?view=net-7.0

Related: dotnet/winforms#8342, #41720

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Issue Details

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The documentation states that many of the functions can return null. So I have updated the nullability based on the documentation.

https://learn.microsoft.com/en-us/dotnet/api/system.componentmodel.design.serialization.idesignerserializationmanager?view=net-7.0

Related: dotnet/winforms#8342, #41720

Author:	elachlan
Assignees:	-
Labels:	area-System.ComponentModel
Milestone:	-

[stephentoub]

Thanks. The changes look correct to me, but you'll also need to update the corresponding signatures in the ref assembly:

runtime/src/libraries/System.ComponentModel.TypeConverter/ref/System.ComponentModel.TypeConverter.cs

Lines 2188 to 2203 in 4689efa

	public partial interface IDesignerSerializationManager : System.IServiceProvider
	{
	System.ComponentModel.Design.Serialization.ContextStack Context { get; }
	System.ComponentModel.PropertyDescriptorCollection Properties { get; }
	event System.ComponentModel.Design.Serialization.ResolveNameEventHandler ResolveName;
	event System.EventHandler SerializationComplete;
	void AddSerializationProvider(System.ComponentModel.Design.Serialization.IDesignerSerializationProvider provider);
	object CreateInstance(System.Type type, System.Collections.ICollection arguments, string name, bool addToContainer);
	object GetInstance(string name);
	string GetName(object value);
	object GetSerializer(System.Type objectType, System.Type serializerType);
	System.Type GetType(string typeName);
	void RemoveSerializationProvider(System.ComponentModel.Design.Serialization.IDesignerSerializationProvider provider);
	void ReportError(object errorInformation);
	void SetName(object instance, string name);
	}

[elachlan]

Failed test is unrelated afaik.

[buyaa-n]

Failed test is unrelated afaik.

Right, they are unrelated and reported #79569, #79403, #79453, merging the PR