Make IllegalArgumentException more forgiving about its arguments.

corelib/src/exceptions.dart

Index: corelib/src/exceptions.dart
===================================================================
--- corelib/src/exceptions.dart	(revision 3850)
+++ corelib/src/exceptions.dart	(working copy)
@@ -71,9 +71,9 @@
 
 
 class IllegalArgumentException implements Exception {
-  const IllegalArgumentException([args = ""]) : _args = args;
-  String toString() => "Illegal argument(s): $_args";
-  final String _args;
+  const IllegalArgumentException([arg = ""]) : _arg = arg;
+  String toString() => "Illegal argument(s): $_arg";
+  final _arg;

[jjb, 2012/02/02 18:36:25]

This is a fine stopgap.  In the long run, we need:

(1) Documentation (for all exception classes).
(2) Better constructors (e.g., IAE  should take a parameter describing what was
expected, as well as what was found.
(3) Better code style (e.g., state variables before functions, comments
describing state variables, etc.)

 }