Return types for IDebugEventContextCallbacks

Hi,

This is a follow up of https://github.com/microsoft/windows-rs/issues/3559.

According to https://learn.microsoft.com/en-us/windows-hardware/drivers/ddi/dbgeng/nf-dbgeng-idebugeventcallbacks-breakpoint, Breakpoint should return something of the form DEBUG_STATUS_XXXX.

The latest winmd files contain the return type of HRESULT, which is correct, but turns into windows_core::Result<()> in the windows_rs bindings, which isn't correct. This is the unit type and doesn't reflect the correct return type.

fn Breakpoint(&self, bp: windows_core::Ref<'_, IDebugBreakpoint2>, context: *const core::ffi::c_void, contextsize: u32) -> windows_core::Result<()>;

in the impl,

pub trait IDebugEventContextCallbacks_Impl: windows_core::IUnknownImpl {
    fn GetInterestMask(&self) -> windows_core::Result<u32>;
    fn Breakpoint(&self, bp: windows_core::Ref<'_, IDebugBreakpoint2>, context: *const core::ffi::c_void, contextsize: u32) -> windows_core::Result<()>;

From ILSpy I can see that the interface matches learn.microsoft.com. However, and this is my assumption, for the rust bindings to be correct, it must have an [Out] parameter in order to be able to produce the correct return type, Result<u32>.

GetInterestMask above is correct.

The question is how can this be fixed? The interfaces do appear to match learn.microsoft.com but the bindings are incomplete in my view.

To me this means I can't implement an override like this,

https://github.com/glslang/win-kexp/blob/main/src/dbgeng.rs#L360

Start with the IDebugEventContextCallbacks metadata in the latest winmd files and compare Breakpoint with the Microsoft Learn signature and the generated windows-rs trait shown in the issue. Check the linked win-kexp implementation and determine what metadata representation is needed for the DEBUG_STATUS_XXXX return; done when the generated binding exposes the expected result type and the override can compile.