twitchlogin: Merge rather than appending

modules/http/twitchlogin.pike

@@ -59,13 +59,13 @@ __async__ mapping(string:mixed) http_request(Protocols.HTTP.Server.Request req)
 		//Check if these credentials are at least what we already had.
 		mapping tok = G->G->user_credentials[(int)user->id] || ([]);
 		array missing = (tok->scopes || ({ })) - (req->variables->scope / " ") - ({""});
-		if (sizeof(missing)) {werror("LOGIN FAIL: %O %O %O\n", tok->scopes, req->variables->scope, (tok->scopes + missing) * " "); return render_template(#"# Twitch Login
+		if (sizeof(missing)) {werror("LOGIN FAIL: %O %O %O\n", tok->scopes, req->variables->scope, (tok->scopes | missing) * " "); return render_template(#"# Twitch Login
 
 Hey, sorry, something seems to be messed up. Rosuav is looking into it. For now, you may
 be able to get logged in by clicking this button:
 
 [Try again](:.twitchlogin data-scopes=@$$scopes$$@)
-", (["scopes": (tok->scopes + missing) * " "]));}
+", (["scopes": (tok->scopes | missing) * " "]));}
 		G->G->DB->save_user_credentials(([
 			"userid": (int)user->id,
 			"login": user->login,