Update Activator.xml

[colejohnson66]

Summary

Document (in the "returns" section) when Activator.CreateInstance can return null. This information is currently documented in the remarks, but, as remarks are placed below exceptions and examples, it's easy to miss.

Fixes #9407

Question

Should the note of null returns be removed from the remarks area?

[learn-build-service-prod]

Learn Build status updates of commit 6412b81:

❌ Validation status: errors

Please follow instructions here which may help to resolve issue.

File	Status	Preview URL	Details
	❌Error		Details
xml/System/Activator.xml	❌Error		Details

• Line 0, Column 0: [Error: ECMA2Yaml_File_LoadFailed] Failed to load 1 files, aborting...

xml/System/Activator.xml

• Line 0, Column 0: [Error: ECMA2Yaml_InternalError]

Intenal Several Error: System.Xml.XmlException: The '%' character, hexadecimal value 0x25, cannot be included in a name. Line 404, position 111.
   at System.Xml.XmlTextReaderImpl.Throw(Exception e)
   at System.Xml.XmlTextReaderImpl.Throw(String res, String[] args)
   at System.Xml.XmlTextReaderImpl.Throw(Int32 pos, String res, String[] args)
   at System.Xml.XmlTextReaderImpl.ParseElement()
   at System.Xml.XmlTextReaderImpl.ParseElementContent()
   at System.Xml.Linq.XContainer.ReadContentFrom(XmlReader r)
   at System.Xml.Linq.XDocument.Load(XmlReader reader, LoadOptions options)
   at System.Xml.Linq.XDocument.Parse(String text, LoadOptions options)
   at ECMA2Yaml.ECMALoader.LoadType(FileItem typeFile)
   at ECMA2Yaml.ECMALoader.LoadTypes(String basePath, Namespace ns)

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[learn-build-service-prod]

Learn Build status updates of commit 556b30a:

✅ Validation status: passed

File	Status	Preview URL	Details
xml/System/Activator.xml	✅Succeeded	View

For more details, please refer to the build report.

For any questions, please:

• Try searching the learn.microsoft.com contributor guides
• Post your question in the Learn support channel

[gewarren]

Thanks @colejohnson66. Yes, can you remove it from the remarks. Also, it looks like there are a couple more overloads that should be updated with this return type.

[learn-build-service-prod]

Learn Build status updates of commit 04b71c6:

✅ Validation status: passed

File	Status	Preview URL	Details
xml/System/Activator.xml	✅Succeeded	View

For more details, please refer to the build report.

For any questions, please:

• Try searching the learn.microsoft.com contributor guides
• Post your question in the Learn support channel

[gewarren]

Thanks!