Hide reflection additions introduced for Windows Store

[pedrobsaila]

Fixes #89975

[dotnet-issue-labeler]

Note regarding the new-api-needs-documentation label:

This serves as a reminder for when your PR is modifying a ref *.cs file and adding/modifying public APIs, please make sure the API implementation in the src *.cs file is documented with triple slash comments, so the PR reviewers can sign off that change.

[dotnet-issue-labeler]

Note regarding the new-api-needs-documentation label:

This serves as a reminder for when your PR is modifying a ref *.cs file and adding/modifying public APIs, please make sure the API implementation in the src *.cs file is documented with triple slash comments, so the PR reviewers can sign off that change.

[jkoritzinsky]

Based on #53217 (comment) (the comment after the one linked in the issue), the CustomAttributeExtensions class shouldn't be marked EB.Never.

[pedrobsaila]

Based on #53217 (comment) (the comment after the one linked in the issue), the CustomAttributeExtensions class shouldn't be marked EB.Never.

It's just a wrapper around static calls of Attribute class, CustomAttributeExtensions doesn't provide anything additional comparing to the Attribute class

[jkoritzinsky]

It provides the generic GetCustomAttribute<T> methods that no one else provides. It's not just a wrapper like the other types.

[pedrobsaila]

It provides the generic GetCustomAttribute<T> methods that no one else provides. It's not just a wrapper like the other types.

This method does just an explicit cast for the Attribute.GetCustomAttribute method result:

(T)Attribute.GetCustomAttribute(element, attributeType);

[jkoritzinsky]

Yes, but this API shape is more convenient and this is the only type that provides it. The other APIs are requested to be hidden as they're the exact same API shape as an existing API and not unique API shapes.

[jkotas]

Suggested change

	[System.ComponentModel.EditorBrowsable(System.ComponentModel.EditorBrowsableState.Never)]
	[System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]

ref sources should use the full type name for attributes including Attribute suffix. It is the style used by the ref sources auto-generator.

(multiple places)

[tannergooding]

Doesn't this need to goto API review for approval first?

We typically treat new attributes, particularly ones like EditorBrowsable, Obsolete, etc as part of the "public API surface" and get explicit sign-off (even where its a clear thing we want to do).

[pedrobsaila]

Doesn't this need to goto API review for approval first?

We typically treat new attributes, particularly ones like EditorBrowsable, Obsolete, etc as part of the "public API surface" and get explicit sign-off (even where its a clear thing we want to do).

I think it was done as part of #53217

[ericstj]

I see in #53217 (comment) that @steveharter mentioned there were some open questions remaining about scope. I'd like his review here.

[steveharter]

I updated #89975 to add the affected APIs and marked that issue as "api-ready-for-review". Once approved, this PR can go in.

[steveharter]

I see in #53217 (comment) that @steveharter mentioned there were some open questions remaining about scope. I'd like his review here.

Yeah based on that I created #89975 to track which I just updated (see above).

[steveharter]

API was approved