Rename RuntimeError to CyclicIntializationError, as per spec.

tests/standalone/io/test_extension_fail_tester.dart

Index: tests/standalone/io/test_extension_fail_tester.dart
diff --git a/tests/standalone/io/test_extension_fail_tester.dart b/tests/standalone/io/test_extension_fail_tester.dart
index aa8daae5c56ca73926996cc3d72fee212fdfe9c8..f2e72aeca5e4732e02af7ad4c3c918dc1b60c7a7 100644
--- a/tests/standalone/io/test_extension_fail_tester.dart
+++ b/tests/standalone/io/test_extension_fail_tester.dart
@@ -12,7 +12,7 @@ main() {
   try {
     Cat.throwMeTheBall("ball");
   } on String catch (e) {
-    if (e != "ball") throw new RuntimeError("exception not equal to 'ball'");
+    if (e != "ball") throw new StateError("exception not equal to 'ball'");
   }
   // Make sure the exception is thrown out to the event handler from C++ code.
   // The harness expects the string "ball" to be thrown and the process to