Add List.insert.

editor/util/plugins/com.google.dart.java2dart/resources/java_core.dart

Index: editor/util/plugins/com.google.dart.java2dart/resources/java_core.dart
diff --git a/editor/util/plugins/com.google.dart.java2dart/resources/java_core.dart b/editor/util/plugins/com.google.dart.java2dart/resources/java_core.dart
index a450fbd85de638cc6afdb9fe190f37f7403ca222..72e9b784eca0200c50cdc4d6282b780c9a292a2f 100644
--- a/editor/util/plugins/com.google.dart.java2dart/resources/java_core.dart
+++ b/editor/util/plugins/com.google.dart.java2dart/resources/java_core.dart
@@ -290,6 +290,10 @@ class ListWrapper<E> extends Collection<E> implements List<E> {
     return elements.remove(element);
   }
 
+  void insert(int index, E value) {

[Lasse Reichstein Nielsen, 2013/03/07 09:57:53]

It's a little inconsistent with removeAt, but I guess it can't be avoided
without overloading.

If we had slice-assignment, it would just be:
  list[index:index] = [value]
We should have slice assignment!

[floitsch, 2013/03/07 12:53:53]

I looked at the other languages (the ones Sean linked to), and I saw some that
had the same API. So I'm ok with it.

+    elements.insert(index, value);
+  }
+
   E removeAt(int index) {
     return elements.removeAt(index);
   }