Revert "Fix reporting of foreign native exception not handled by runt…

[tommcdon]

This PR reverts #115750 which affected debugger scenarios, causing internal Visual Studio testing to fail

This reverts commit 90236b9.

[Copilot]

Pull Request Overview

This PR reverts commit 90236b9… which introduced changes to foreign native exception reporting, restoring the previous debugger-friendly behavior.

• Removes thread-based native exception helpers and associated C# test.
• Reverts the modified isNotHandledByRuntime logic in the exception handling path.

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
src/tests/baseservices/exceptions/exceptioninterop/ExceptionInteropNative.cpp	Deletes InvokeCallbackAndCatchNative and InvokeCallbackOnNewThread to revert test helpers
src/tests/baseservices/exceptions/exceptioninterop/ExceptionInterop.cs	Removes the InvokeCallbackOnNewThread DllImport and its PropagateAndCatchCppException test
src/coreclr/vm/exceptionhandling.cpp	Restores the original branching logic around detecting unhandled managed exceptions

Comments suppressed due to low confidence (2)

src/tests/baseservices/exceptions/exceptioninterop/ExceptionInterop.cs:193

• [nitpick] By removing the PropagateAndCatchCppException test, coverage for native exception propagation is reduced. Consider adding an alternative test or updating existing tests to ensure this behavior remains exercised.

[DllImport(nameof(ExceptionInteropNative))]

src/coreclr/vm/exceptionhandling.cpp:4018

• The condition no longer checks that the exception is a managed (COM+) exception; the IsComPlusException guard was removed, which may cause non-managed exceptions to be treated as unhandled. Consider restoring the IsComPlusException(pTopExInfo->m_ptrs.ExceptionRecord) check in this if condition.

if ((pFrame == FRAME_TOP) ||