Clean up leg.dart.

dart/lib/compiler/implementation/types/concrete_types_inferrer.dart

Index: dart/lib/compiler/implementation/types/concrete_types_inferrer.dart
diff --git a/dart/lib/compiler/implementation/types/concrete_types_inferrer.dart b/dart/lib/compiler/implementation/types/concrete_types_inferrer.dart
index 82387de2f3080f3bc99535debd4e030811a9b57f..780241d3355d694c274507156a7a36e253a5383b 100644
--- a/dart/lib/compiler/implementation/types/concrete_types_inferrer.dart
+++ b/dart/lib/compiler/implementation/types/concrete_types_inferrer.dart
@@ -764,7 +764,6 @@ class ConcreteTypesInferrer {
    * Fail with a message and abort.
    */
   void fail(node, [reason]) {
-    throw "fail: ${node.toDebugString()}";
     String message = 'cannot infer types';
     if (reason != null) {
       message = '$message: $reason';
@@ -781,7 +780,7 @@ class ArgumentsTypes {
   final List<ConcreteType> positional;
   final Map<Identifier, ConcreteType> named;
   ArgumentsTypes(this.positional, this.named);
-  int get length() => positional.length + named.length;
+  int get length => positional.length + named.length;
   toString() => "{ positional = $positional, named = $named }";
 }