Interop source generator should insert [GeneratedCodeAttribute]

[danmoseley]

As noted in #64541,

• this makes it consistent with our other generators
• metadata tools cannot see <autogenerated>, which is hte preferred source marking
• there are scenarios where one might scan assemblies to see whether it is necessary to regenerate with a bug-fixed generator

example, from the regex generator

runtime/src/libraries/System.Text.RegularExpressions/gen/RegexGenerator.Emitter.cs

Line 27 in 9df2832

private static readonly string s_generatedCodeAttribute = $"[global::System.CodeDom.Compiler.GeneratedCodeAttribute(\"{typeof(RegexGenerator).Assembly.GetName().Name}\", \"{typeof(RegexGenerator).Assembly.GetName().Version}\")]";

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Issue Details

---

As noted in #64541,

• this makes it consistent with our other generators
• metadata tools cannot see <autogenerated>, which is hte preferred source marking
• there are scenarios where one might scan assemblies to see whether it is necessary to regenerate with a bug-fixed generator

example, from the regex generator

runtime/src/libraries/System.Text.RegularExpressions/gen/RegexGenerator.Emitter.cs

Line 27 in 9df2832

private static readonly string s_generatedCodeAttribute = $"[global::System.CodeDom.Compiler.GeneratedCodeAttribute(\"{typeof(RegexGenerator).Assembly.GetName().Name}\", \"{typeof(RegexGenerator).Assembly.GetName().Version}\")]";

Author:	danmoseley
Assignees:	-
Labels:	area-System.Runtime.InteropServices
Milestone:	-