Lower map literals to constructor or function calls in builder

pkg/compiler/lib/src/tree_ir/tree_ir_builder.dart

 // Copyright (c) 2014, 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 tree_ir_builder;
 
 import '../common.dart';
 import '../constants/values.dart';
 import '../cps_ir/cps_ir_nodes.dart' as cps_ir;
 import '../elements/elements.dart';
@@ skipping 525 matching lines @@
   Expression visitConstant(cps_ir.Constant node) {
     return new Constant(node.value, sourceInformation: node.sourceInformation);
   }
 
   Expression visitLiteralList(cps_ir.LiteralList node) {
     return new LiteralList(
             node.dartType,
             translateArguments(node.values));
   }
 
-  Expression visitLiteralMap(cps_ir.LiteralMap node) {
-    return new LiteralMap(
-        node.dartType,
-        new List<LiteralMapEntry>.generate(node.entries.length, (int index) {
-          return new LiteralMapEntry(
-              getVariableUse(node.entries[index].key),
-              getVariableUse(node.entries[index].value));
-        })
-    );
-  }
-
   Expression visitReifyRuntimeType(cps_ir.ReifyRuntimeType node) {
     return new ReifyRuntimeType(
         getVariableUse(node.value), node.sourceInformation);
   }
 
   Expression visitReadTypeVariable(cps_ir.ReadTypeVariable node) {
     return new ReadTypeVariable(
         node.variable,
         getVariableUse(node.target),
         node.sourceInformation);
@@ skipping 181 matching lines @@
 
   visitFunctionDefinition(cps_ir.FunctionDefinition node) {
     unexpectedNode(node);
   }
   visitParameter(cps_ir.Parameter node) => unexpectedNode(node);
   visitContinuation(cps_ir.Continuation node) => unexpectedNode(node);
   visitMutableVariable(cps_ir.MutableVariable node) => unexpectedNode(node);
   visitRethrow(cps_ir.Rethrow node) => unexpectedNode(node);
   visitBoundsCheck(cps_ir.BoundsCheck node) => unexpectedNode(node);
 }