Delete CPS IR

tests/compiler/dart2js/cps_ir/input/argument_refinement_num_15.dart

Index: tests/compiler/dart2js/cps_ir/input/argument_refinement_num_15.dart
diff --git a/tests/compiler/dart2js/cps_ir/input/argument_refinement_num_15.dart b/tests/compiler/dart2js/cps_ir/input/argument_refinement_num_15.dart
deleted file mode 100644
index 227e62e2d7e727a6ba27c621050ddba6fea2d77d..0000000000000000000000000000000000000000
--- a/tests/compiler/dart2js/cps_ir/input/argument_refinement_num_15.dart
+++ /dev/null
@@ -1,12 +0,0 @@
-main() {
-  var x = int.parse('1233');
-  var y = int.parse('1234');
-  var z = int.parse('1236');
-  print(x is num);
-  print(y is num);
-  print(z is num);
-  print(x.clamp(y, z));
-  print(x is num);
-  print(y is num); // will be compiled to `true` if we know the type of `y`.
-  print(z is num);
-}