Transscript wmcontainer to IDL and verify interfaces


git-svn-id: https://svn.code.sf.net/p/mingw-w64/code@6509 4407c894-4637-0410-b4f5-ada5f102cad1
Make DECLSPEC_DLLIMPORT widl-comppatible.


git-svn-id: https://svn.code.sf.net/p/mingw-w64/code@6510 4407c894-4637-0410-b4f5-ada5f102cad1