dart2js cps: Add instruction for bounds checks.

pkg/compiler/lib/src/cps_ir/cps_fragment.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library cps_ir.cps_fragment;
 
 import 'cps_ir_nodes.dart';
 import '../constants/values.dart';
 import '../universe/selector.dart' show Selector;
 import '../types/types.dart' show TypeMask;
@@ skipping 86 matching lines @@
     return prim;
   }
 
   /// Bind a constant value.
   Primitive makeConstant(ConstantValue constant) {
     return letPrim(new Constant(constant));
   }
 
   Primitive makeZero() => makeConstant(new IntConstantValue(0));
   Primitive makeOne() => makeConstant(new IntConstantValue(1));
+  Primitive makeMinusOne() => makeConstant(new IntConstantValue(-1));
   Primitive makeNull() => makeConstant(new NullConstantValue());
   Primitive makeTrue() => makeConstant(new TrueConstantValue());
   Primitive makeFalse() => makeConstant(new FalseConstantValue());
 
   /// Invoke a built-in operator.
   Primitive applyBuiltin(BuiltinOperator op, List<Primitive> args) {
     return letPrim(new ApplyBuiltinOperator(op, args, sourceInformation));
   }
 
+  Primitive refine(Primitive value, TypeMask type) {
+    return letPrim(new Refinement(value, type));
+  }
+
   Primitive invokeBuiltin(BuiltinMethod method,
                           Primitive receiver,
                           List<Primitive> arguments,
                           {bool receiverIsNotNull: false}) {
     ApplyBuiltinMethod apply =
         new ApplyBuiltinMethod(method, receiver, arguments, sourceInformation);
     apply.receiverIsNotNull = receiverIsNotNull;
     return letPrim(apply);
   }
 
@@ skipping 208 matching lines @@
   }
 }
 
 /// Removes [node], unlinking all its references and replaces it with [newNode].
 void destroyAndReplace(Expression node, Expression newNode) {
   InteriorNode parent = node.parent;
   RemovalVisitor.remove(node);
   parent.body = newNode;
   newNode.parent = parent;
 }