Added more WMF declarations.

git-svn-id: svn+ssh://svn.code.sf.net/p/mingw-w64/code/trunk@5605 4407c894-4637-0410-b4f5-ada5f102cad1
diff --git a/mingw-w64-headers/include/mfobjects.idl b/mingw-w64-headers/include/mfobjects.idl
index a9d744e..9b0f40f 100644
--- a/mingw-w64-headers/include/mfobjects.idl
+++ b/mingw-w64-headers/include/mfobjects.idl
@@ -539,6 +539,18 @@
     HRESULT RemoveAllElements();
 }
 
+[
+    object,
+    uuid(7fee9e9a-4a89-47a6-899c-b6a53a70fb67),
+    pointer_default(unique)
+]
+interface IMFActivate : IMFAttributes
+{
+    HRESULT ActivateObject([in] REFIID riid, [out, iid_is(riid), retval] void ** ppv);
+    HRESULT ShutdownObject();
+    HRESULT DetachObject();
+}
+
 typedef enum _MF_Plugin_Type {
     MF_Plugin_Type_MFT           = 0,
     MF_Plugin_Type_MediaSource   = 1