Remove browser engine detection

It is out of date and not used anyway.

tests/input.html

@@ -39,9 +39,6 @@
             canvas, keyboard, mouse;
 
         var newline = "\n";
-        if (Util.Engine.trident) {
-            var newline = "<br>\n";
-        }
 
         function message(str) {
             console.log(str);