Respect ISupportErrorInfo for HRESULT to Exception throwing conversion

[jkoritzinsky]

Add the API proposed in #117438

Update built-in COM to use it.

Update source-generated COM to use it.

Fixes #117438
Fixes #116917

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[Copilot]

Pull Request Overview

This PR implements support for respecting the ISupportErrorInfo interface when converting HRESULT values to exceptions in COM interop scenarios. The changes add a new overload to Marshal.GetExceptionForHR and Marshal.ThrowExceptionForHR that takes an interface ID and COM object pointer to check if the interface supports error information before using the error details.

Key changes include:

• Adding new public API overloads that check ISupportErrorInfo before using error information
• Updating both built-in COM and source-generated COM to use the enhanced error handling
• Removing legacy native code implementations in favor of managed implementations

Reviewed Changes

Copilot reviewed 16 out of 16 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
System.Runtime.InteropServices.cs	Adds new public API overloads for GetExceptionForHR and ThrowExceptionForHR with ISupportErrorInfo support
Marshal.cs	Implements the core logic for checking ISupportErrorInfo and calling appropriate error handling
StubHelpers.cs	Updates COM stub helpers to use new managed implementation instead of native QCall
ManagedHResultExceptionGeneratorResolver.cs	Updates source generator to pass interface ID and object pointer to new API
ThrowExceptionForHRTests.cs	Adds comprehensive tests for the new ISupportErrorInfo functionality
Multiple native files	Removes obsolete native QCall implementations for COM exception handling

Comments suppressed due to low confidence (1)

src/libraries/System.Runtime.InteropServices/tests/System.Runtime.InteropServices.UnitTests/System/Runtime/InteropServices/Marshal/ThrowExceptionForHRTests.cs:114

• This test assertion checks that an InvalidOperationException is returned when using an ArgumentException's HResult. This seems inconsistent - if the error info contains an InvalidOperationException but we're passing an ArgumentException's HResult, the test should verify that the error info takes precedence over the HResult when ISupportErrorInfo returns S_OK.

                Assert.IsType<InvalidOperationException>(Marshal.GetExceptionForHR(new ArgumentException().HResult, iid, pUnk));

[AaronRobinsonMSFT]

Thank you!

[jtschuster]

We should leave #116917 open until we have tests for the generator or file a new issue to track adding tests.

[AaronRobinsonMSFT]

We should leave #116917 open until we have tests for the generator or file a new issue to track adding tests.

This has added testing for the API. I don't think we need testing for the COM source generator in this case. The fact that we use the API should be sufficient.

[AaronRobinsonMSFT]

We should leave #116917 open until we have tests for the generator or file a new issue to track adding tests.

This has added testing for the API. I don't think we need testing for the COM source generator in this case. The fact that we use the API should be sufficient.

I'm saying this is okay because we already have error related testing. I don't think specifically testing the IErrorInfo behavior in this specific scenario is really needed.

[jkoritzinsky]

/ba-g wasm timeouts for legs that don't run these tests.