Delete CPS IR

tests/compiler/dart2js/cps_ir/expected/argument_refinement_1.js

-// Expectation for test: 
-// main() {
-//   var x = int.parse('1233');
-//   var y = int.parse('1234');
-//   print(x is num);
-//   print(y is num);
-//   print(x - y);
-//   print(x is num);
-//   print(y is num); // will be compiled to `true` if we know the type of `y`.
-// }
-
-function() {
-  var x = P.int_parse("1233", null, null), y = P.int_parse("1234", null, null);
-  P.print(typeof x === "number");
-  P.print(typeof y === "number");
-  if (typeof x !== "number" || typeof y !== "number")
-    return J.$sub$n(x, y);
-  P.print(x - y);
-  P.print(true);
-  P.print(true);
-}