[Bug 49998] New: widl doesn't support winrt types (runtimeclass, delegate, parameterized types, ...)

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=49998

Bug ID: 49998
           Summary: widl doesn't support winrt types (runtimeclass,
                    delegate, parameterized types, ...)
           Product: Wine
           Version: 5.19
          Hardware: x86-64
                OS: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: -unknown
          Assignee: [e-mail]
          Reporter: [e-mail]
      Distribution: ---

Created attachment 68403
  --> https://bugs.winehq.org/attachment.cgi?id=68403
PoC implementation of WinRT subset in widl

In winrt mode (using --winrt or #pragma winrt), widl is unable to parse several
winrt-specific keywords and generate the corresponding interface headers.

I'm opening this bug mainly to provide my implementation (attached) as a proof
of concept, and so that it can then be tested more extensively, helping it go
upstream eventually.

I'll also attach updated series for the few WinRT stub dlls in staging,
re-implemented using idl files thanks to the new support in widl.