Backout constant support

tests/language/compile_time_constant12_test.dart

Index: tests/language/compile_time_constant12_test.dart
diff --git a/tests/language/compile_time_constant12_test.dart b/tests/language/compile_time_constant12_test.dart
index cbe1a817c2ed2d7e91be447f410f298f2827dd37..0ae5f5772f6d725fb5272e1a193b8a8a9a2cf75a 100644
--- a/tests/language/compile_time_constant12_test.dart
+++ b/tests/language/compile_time_constant12_test.dart
@@ -3,10 +3,11 @@
 // BSD-style license that can be found in the LICENSE file.
 
 const String s = "foo";
-const int i = s.length;
+const int i = s.length; /// 01: compile-time error
 
 use(x) => x;
 
 main() {
-  use(i);
+  use(s);
+  use(i); /// 01: continued
 }