mshtml: Expose nsIFormPOSTActionChannel interface from nsChannel object.

dlls/mshtml/nsiface.idl

@@ -723,6 +723,15 @@ interface nsIUploadChannel : nsISupports
 
 [
     object,
+    uuid(fc826b53-0db8-42b4-aa6a-5dd2cfca52a4),
+    local
+]
+interface nsIFormPOSTActionChannel : nsIUploadChannel
+{
+}
+
+[
+    object,
     uuid(8d171460-a716-41f1-92be-8c659db39b45),
     local
 ]

dlls/mshtml/nsio.c

@@ -540,6 +540,9 @@ static nsresult NSAPI nsChannel_QueryInterface(nsIHttpChannel *iface, nsIIDRef r
     }else if(IsEqualGUID(&IID_nsIUploadChannel, riid)) {
         TRACE("(%p)->(IID_nsIUploadChannel %p)\n", This, result);
         *result = &This->nsIUploadChannel_iface;
+    }else if(IsEqualGUID(&IID_nsIFormPOSTActionChannel, riid)) {
+        TRACE("(%p)->(IID_nsIFormPOSTActionChannel %p)\n", This, result);
+        *result = &This->nsIUploadChannel_iface;
     }else if(IsEqualGUID(&IID_nsIHttpChannelInternal, riid)) {
         TRACE("(%p)->(IID_nsIHttpChannelInternal %p)\n", This, result);
         *result = is_http_channel(This) ? &This->nsIHttpChannelInternal_iface : NULL;