more care around generated names, fixes #60 #82 and #97

test/codegen/try_catch.dart

Index: test/codegen/try_catch.dart
diff --git a/test/codegen/try_catch.dart b/test/codegen/try_catch.dart
index c67493f9c19e079b80ebabd1523994d05470cdc3..844d7f24d1e59e2e0064a2783467efb0c79c1f11 100644
--- a/test/codegen/try_catch.dart
+++ b/test/codegen/try_catch.dart
@@ -1,4 +1,8 @@
-main() {
+// Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+foo() {
   try {
     throw "hi there";
   } on String catch (e, t) {
@@ -6,4 +10,16 @@ main() {
     rethrow;
   }
 }
-
+bar() {
+  try {
+    throw "hi there";
+  } catch (e, t) {
+  } on String catch (e, t) {
+    // unreachable
+    rethrow;
+  }
+}
+main() {
+  foo();
+  bar();
+}