mshtml: Check for EVENTID_LAST in ensure_doc_nsevent_handler().

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=50110
Signed-off-by: Paul Gofman <pgofman@codeweavers.com>
Signed-off-by: Jacek Caban <jacek@codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>

dlls/mshtml/htmlevent.c

@@ -2832,6 +2832,8 @@ HRESULT ensure_doc_nsevent_handler(HTMLDocumentNode *doc, nsIDOMNode *nsnode, ev
         doc->event_vector[eid] = TRUE;
         eid = EVENTID_BLUR;
         break;
+    case EVENTID_LAST:
+        return S_OK;
     default:
         break;
     }