Revert variance changes for trimming attributes validation

[Copilot]

Description

Reverts attempted variance handling for DynamicallyAccessedMembers and Requires* attributes in override/interface implementation scenarios.

The variance approach was incorrect:

• Requires attributes*: Removing from interface implementations would allow callers to cast to the interface and bypass warnings while executing the same code
• DynamicallyAccessedMembers: Exact matching ensures consistent behavior regardless of access path (base, derived, or interface)

Changes

• Restored original exact-match validation for FlowAnnotations.ValidateMethodAnnotationsAreSame in ILLink and NativeAOT
• Restored original DynamicallyAccessedMembersAnalyzer.VerifyDamOnMethodsMatch in Roslyn Analyzer
• Restored original test expectations in VirtualMethodHierarchyDataflowAnnotationValidation and RequiresAttributeMismatch

Test Results

• All 81 DataFlow tests: PASSED
• All 23 RequiresCapability tests: PASSED

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Trimming attributes don't fully handle variance</issue_title>
<issue_description>Most of the trimming analysis is too conservative in how it handles attributes in override/interface situations.

In overriding, hiding, and interface implementation (OHI):

• DynamicallyAccessedMembers should allow adding DAMT items in member outputs and removing DAMT items on inputs, but not vice versa.
• Removing Requires* from an OHI member should be allowed, but not adding</issue_description>

Comments on the Issue (you are @copilot in this section)

@agocke That would be unsafe. You could always cast down to the interface and remove the warning. This is follows from the general variance rules. You can loosen input requirements in subtypes, but you can’t strengthen. For example, you could change a parameter type from string to object, but not vice versa (note, c# only allows this for interfaces)

• Fixes Trimming attributes don't fully handle variance #120203

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[agocke]

@copilot

 Failed RequiresCapability.RequiresAttributeMismatch [2 s]
  Error Message:
   Expected to find warning: warning IL2046: Mono.Linker.Tests.Cases.RequiresCapability.RequiresAttributeMismatch.ImplementationClassWithoutRequires.Method(): and message containing 'ImplementationClassWithoutRequires.Method()' 'IBaseWithRequires.Method()', but no such message was found.
Expected to find warning: warning IL2046: Mono.Linker.Tests.Cases.RequiresCapability.RequiresAttributeMismatch.ImplementationClassWithoutRequires.PropertyAnnotationInAccesor.get: and message containing 'ImplementationClassWithoutRequires.PropertyAnnotationInAccesor.get' 'IBaseWithRequires.PropertyAnnotationInAccesor.get', but no such message was found.
Expected to find warning: warning IL2046: Mono.Linker.Tests.Cases.RequiresCapability.RequiresAttributeMismatch.ImplementationClassWithoutRequires.PropertyAnnotationInPropertyAndAccessor.set: and message containing 'ImplementationClassWithoutRequires.PropertyAnnotationInPropertyAndAccessor.set' 'IBaseWithRequires.PropertyAnnotationInPropertyAndAccessor.set', but no such message was found.
Expected to find warning: warning IL2046: Mono.Linker.Tests.Cases.RequiresCapability.RequiresAttributeMismatch.ExplicitImplementationClassWithoutRequires.Mono.Linker.Tests.Cases.RequiresCapability.RequiresAttributeMismatch.IBaseWithRequires.Method(): and message containing 'IBaseWithRequires.Method()' 'ExplicitImplementationClassWithoutRequires.Mono.Linker.Tests.Cases.RequiresCapability.RequiresAttributeMismatch.IBaseWithRequires.Method()', but no such message was found.
Expected to find warning: warning IL2046: Mono.Linker.Tests.Cases.RequiresCapability.RequiresAttributeMismatch.ExplicitImplementationClassWithoutRequires..Linker.Tests.Cases.RequiresCapability.RequiresAttributeMismatch.IBaseWithRequires.get_PropertyAnnotationInAccesor.get: and message containing 'PropertyAnnotationInAccesor.get' 'IBaseWithRequires.PropertyAnnotationInAccesor.get', but no such message was found.
Expected to find warning: warning IL2046: Mono.Linker.Tests.Cases.RequiresCapability.RequiresAttributeMismatch.ExplicitImplementationClassWithoutRequires..Linker.Tests.Cases.RequiresCapability.RequiresAttributeMismatch.IBaseWithRequires.set_PropertyAnnotationInPropertyAndAccessor.set: and message containing 'PropertyAnnotationInPropertyAndAccessor.set' 'IBaseWithRequires.PropertyAnnotationInPropertyAndAccessor.set', but no such message was found.
Expected to find warning: warning IL2046: Mono.Linker.Tests.Cases.RequiresCapability.RequiresAttributeMismatch.ImplementationClassWithoutRequiresInSource.Method(): and message containing 'ImplementationClassWithoutRequiresInSource.Method()' 'IBaseWithRequiresInReference.Method()', but no such message was found.
Expected to find warning: warning IL2046: Mono.Linker.Tests.Cases.RequiresCapability.RequiresAttributeMismatch.ImplementationClassWithoutRequiresInSource.PropertyAnnotationInAccesor.get: and message containing 'ImplementationClassWithoutRequiresInSource.PropertyAnnotationInAccesor.get' 'IBaseWithRequiresInReference.PropertyAnnotationInAccesor.get', but no such message was found.
Expected to find warning: warning IL2046: Mono.Linker.Tests.Cases.RequiresCapability.RequiresAttributeMismatch.StaticInterfaceMethods.ImplIRequiresMismatching.VirtualMethod(): and message containing 'ImplIRequiresMismatching.VirtualMethod' 'IRequires.VirtualMethod', but no such message was found.
Expected to find warning: warning IL2046: Mono.Linker.Tests.Cases.RequiresCapability.RequiresAttributeMismatch.StaticInterfaceMethods.ImplIRequiresMismatching.AbstractMethod(): and message containing 'ImplIRequiresMismatching.AbstractMethod' 'IRequires.AbstractMethod', but no such message was found.
Unmatched Messages:

  Stack Trace:
     at Mono.Linker.Tests.TestCasesRunner.ResultChecker.VerifyLoggedMessages(AssemblyDefinition original, TrimmingTestLogger logger, Boolean checkRemainingErrors) in /_/src/tools/illink/test/Mono.Linker.Tests/TestCasesRunner/ResultChecker.cs:line 1196
   at Mono.Linker.Tests.TestCasesRunner.ResultChecker.Check(TrimmedTestCaseResult linkResult) in /_/src/tools/illink/test/Mono.Linker.Tests/TestCasesRunner/ResultChecker.cs:line 131
   at Mono.Linker.Tests.TestCases.All.RequiresCapabilityTests(TestCase testCase) in /_/src/tools/illink/test/Mono.Linker.Tests/TestCases/TestSuites.cs:line 196
   at InvokeStub_All.RequiresCapabilityTests(Object, Span`1)

1)    at Mono.Linker.Tests.TestCasesRunner.ResultChecker.VerifyLoggedMessages(AssemblyDefinition original, TrimmingTestLogger logger, Boolean checkRemainingErrors) in /_/src/tools/illink/test/Mono.Linker.Tests/TestCasesRunner/ResultChecker.cs:line 1196
   at Mono.Linker.Tests.TestCasesRunner.ResultChecker.Check(TrimmedTestCaseResult linkResult) in /_/src/tools/illink/test/Mono.Linker.Tests/TestCasesRunner/ResultChecker.cs:line 131
   at Mono.Linker.Tests.TestCases.All.RequiresCapabilityTests(TestCase testCase) in /_/src/tools/illink/test/Mono.Linker.Tests/TestCases/TestSuites.cs:line 196
   at InvokeStub_All.RequiresCapabilityTests(Object, Span`1)

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Draft Pull Request was automatically closed for 30 days of inactivity. Please let us know if you'd like to reopen it.