Add type info to JSArray.

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

Index: pkg/compiler/lib/src/tree_ir/tree_ir_nodes.dart
diff --git a/pkg/compiler/lib/src/tree_ir/tree_ir_nodes.dart b/pkg/compiler/lib/src/tree_ir/tree_ir_nodes.dart
index 63b7528d0711955e8457fc49d0e0b6d417b1e67b..2b4d3011163dacab55b80c6e8c29af5ae84148b6 100644
--- a/pkg/compiler/lib/src/tree_ir/tree_ir_nodes.dart
+++ b/pkg/compiler/lib/src/tree_ir/tree_ir_nodes.dart
@@ -13,6 +13,8 @@ import '../universe/selector.dart' show Selector;
 
 import '../cps_ir/builtin_operator.dart';
 export '../cps_ir/builtin_operator.dart';
+import '../cps_ir/cps_ir_nodes.dart' show TypeExpressionKind;
+export '../cps_ir/cps_ir_nodes.dart' show TypeExpressionKind;
 
 // These imports are only used for the JavaScript specific nodes.  If we want to
 // support more than one native backend, we should probably create better
@@ -114,7 +116,8 @@ class Variable extends Node {
     assert(host != null);
   }
 
-  String toString() => element == null ? 'Variable' : element.toString();
+  String toString() =>
+      element == null ? 'Variable.${hashCode}' : element.toString();
 }
 
 /// Read the value of a variable.
@@ -669,7 +672,7 @@ class CreateBox extends Expression {
 class CreateInstance extends Expression {
   ClassElement classElement;
   List<Expression> arguments;
-  List<Expression> typeInformation;
+  Expression typeInformation;
   SourceInformation sourceInformation;
 
   CreateInstance(this.classElement, this.arguments,
@@ -902,10 +905,11 @@ class ForeignStatement extends ForeignCode implements Statement {
 /// are replaced by the values in [arguments].
 /// (See documentation on the TypeExpression CPS node for more details.)
 class TypeExpression extends Expression {
+  final TypeExpressionKind kind;
   final DartType dartType;
   final List<Expression> arguments;
 
-  TypeExpression(this.dartType, this.arguments);
+  TypeExpression(this.kind, this.dartType, this.arguments);
 
   accept(ExpressionVisitor visitor) {
     return visitor.visitTypeExpression(this);
@@ -1216,7 +1220,7 @@ abstract class RecursiveVisitor implements StatementVisitor, ExpressionVisitor {
 
   visitCreateInstance(CreateInstance node) {
     node.arguments.forEach(visitExpression);
-    node.typeInformation.forEach(visitExpression);
+    if (node.typeInformation != null) visitExpression(node.typeInformation);
   }
 
   visitReifyRuntimeType(ReifyRuntimeType node) {
@@ -1457,7 +1461,9 @@ class RecursiveTransformer extends Transformer {
 
   visitCreateInstance(CreateInstance node) {
     _replaceExpressions(node.arguments);
-    _replaceExpressions(node.typeInformation);
+    if (node.typeInformation != null) {
+      node.typeInformation = visitExpression(node.typeInformation);
+    }
     return node;
   }