dart2js: Refactoring, documentation, and a few bugfixes in Namer class.

tests/language/constructor_name_clash_lib.dart

Index: tests/language/constructor_name_clash_lib.dart
diff --git a/tools/canary.dart b/tests/language/constructor_name_clash_lib.dart
similarity index 67%
copy from tools/canary.dart
copy to tests/language/constructor_name_clash_lib.dart
index cca1f90cd7be8eb2481a00a89bbc7ba7edaa6d4f..46ea6c0b3c621fcd1827750c10de66980b5b3057 100644
--- a/tools/canary.dart
+++ b/tests/language/constructor_name_clash_lib.dart
@@ -2,10 +2,13 @@
 // 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.
 
-// Script which exits with code 42.
+library lib;
 
-import 'dart:io';
+var global = 0;
 
-void main() {
-  exitCode = 42;
+class A {
+  A() {
+    global += 10;
+    try {} catch(e) {} // no inline
+  }
 }