dart2js cps: Handle error cases.

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

Index: pkg/compiler/lib/src/tree_ir/tree_ir_tracer.dart
diff --git a/pkg/compiler/lib/src/tree_ir/tree_ir_tracer.dart b/pkg/compiler/lib/src/tree_ir/tree_ir_tracer.dart
index 703885ee072af7ddbcda6f8b6a1853bc39988ad4..3a17fc9a615ef9cdcff81cefd0a1b87d3fe08de6 100644
--- a/pkg/compiler/lib/src/tree_ir/tree_ir_tracer.dart
+++ b/pkg/compiler/lib/src/tree_ir/tree_ir_tracer.dart
@@ -360,17 +360,7 @@ class SubexpressionVisitor extends ExpressionVisitor<String> {
   }
 
   String formatArguments(Invoke node) {
-    List<String> args = new List<String>();
-    int positionalArgumentCount = node.selector.positionalArgumentCount;
-    for (int i = 0; i < positionalArgumentCount; ++i) {
-      args.add(node.arguments[i].accept(this));
-    }
-    for (int i = 0; i < node.selector.namedArgumentCount; ++i) {
-      String name = node.selector.namedArguments[i];
-      String arg = node.arguments[positionalArgumentCount + i].accept(this);
-      args.add("$name: $arg");
-    }
-    return args.join(', ');
+    return node.arguments.map(visitExpression).join(', ');
   }
 
   String visitInvokeStatic(InvokeStatic node) {
@@ -535,6 +525,12 @@ class SubexpressionVisitor extends ExpressionVisitor<String> {
   String visitTypeExpression(TypeExpression node) {
     return node.dartType.toString();
   }
+
+  @override
+  String visitCreateInvocationMirror(CreateInvocationMirror node) {
+    String args = node.arguments.map(visitExpression).join(', ');
+    return 'CreateInvocationMirror(${node.selector.name}, $args)';
+  }
 }
 
 /**