Typecheck constructor initializers properly

test/dart_codegen/expect/core/stopwatch.dart

Index: test/dart_codegen/expect/core/stopwatch.dart
diff --git a/test/dart_codegen/expect/core/stopwatch.dart b/test/dart_codegen/expect/core/stopwatch.dart
index a9d63152da5421a03742383829c8e88b7dba309b..0b385d645f90cc3a56f9fdc88227d64754542f70 100644
--- a/test/dart_codegen/expect/core/stopwatch.dart
+++ b/test/dart_codegen/expect/core/stopwatch.dart
@@ -27,7 +27,7 @@ part of dart.core;
   if (_start == null) {
     return 0;
     }
-   return ((__x8) => DDC$RT.cast(__x8, num, int, "CastGeneral", """line 102, column 12 of dart:core/stopwatch.dart: """, __x8 is int, true))((_stop == null) ? (_now() - _start) : (_stop - _start));
+   return ((__x13) => DDC$RT.cast(__x13, num, int, "CastGeneral", """line 102, column 12 of dart:core/stopwatch.dart: """, __x13 is int, true))((_stop == null) ? (_now() - _start) : (_stop - _start));
   }
  Duration get elapsed {
   return new Duration(microseconds: elapsedMicroseconds);