Remove addLast from List.

sdk/lib/_collection_dev/list.dart

Index: sdk/lib/_collection_dev/list.dart
diff --git a/sdk/lib/_collection_dev/list.dart b/sdk/lib/_collection_dev/list.dart
index 0617750aa732e4253a99eba948d3aecf3b037165..d8fe4f89a7cce1dbe39a086581baa8641e14ea52 100644
--- a/sdk/lib/_collection_dev/list.dart
+++ b/sdk/lib/_collection_dev/list.dart
@@ -459,11 +459,6 @@ abstract class FixedLengthListMixin<E>  {
         "Cannot add to a fixed-length list");
   }
 
-  void addLast(E value) {
-    throw new UnsupportedError(
-        "Cannot add to a fixed-length list");
-  }
-
   void insert(int index, E value) {
     throw new UnsupportedError(
         "Cannot add to a fixed-length list");
@@ -549,11 +544,6 @@ abstract class UnmodifiableListMixin<E> {
         "Cannot add to an unmodifiable list");
   }
 
-  void addLast(E value) {
-    throw new UnsupportedError(
-        "Cannot add to an unmodifiable list");
-  }
-
   E insert(int index, E value) {
     throw new UnsupportedError(
         "Cannot add to an unmodifiable list");