Remove PublicAPI files for analyzers project

[Youssef1313]

Follow-up to #6148

[Youssef1313]

Very interesting this is failing despite us setting dotnet_public_api_analyzer.require_api_files = true.

[Youssef1313]

I investigated this. The first source file passed to Csc is /mnt/vss/_work/1/s/.packages/polyfill/9.0.0-beta.14/contentFiles/cs/netstandard2.0/Polyfill/CallerArgumentExpressionAttribute.cs.

The analyzer implementation tries to get the editorconfig for the first source file here:

https://github.com/dotnet/roslyn/blob/6ad21c462cc84c2e22d12e7a1891547c9995c9a7/src/RoslynAnalyzers/PublicApiAnalyzers/Core/Analyzers/DeclarePublicApiAnalyzer.cs#L320-L327

However, polyfill is shipping an .editorconfig inside the package:

https://github.com/SimonCropp/Polyfill/blob/5168b2694414701125457937e704199f93a3aaa4/src/Polyfill/Polyfill.nuspec#L40-L41
https://github.com/SimonCropp/Polyfill/blob/5168b2694414701125457937e704199f93a3aaa4/src/Polyfill/exclude.editorconfig#L2

The editorconfig from polyfill is then considered and our dotnet_public_api_analyzer.require_api_files = true isn't considered.

testfx/.editorconfig

Line 469 in 8ce85d6

dotnet_public_api_analyzer.require_api_files = true

Even if polyfill doesn't ship .editorconfig, I'm not sure how the "syntaxTrees.FirstOrDefault()" implementation on roslyn side will be able to find the right .editorconfig in this case.

@CyrusNajmabadi @333fred Can you please advise here? My feeling is that the correct way is to add require_api_files to .globalconfig (whose options are project-specific rather than syntax-tree/file specific) and Roslyn should then first respect .globalconfig, and fallback to .editorconfig for compatibility.

[Youssef1313]

It looks like .globalconfig already work, at least locally. Let's see CI.