Add List.shuffle().

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 be03c5002b3a1a8a0eef18c8fb46bdfe4c3b5afe..c136b7a37ff39db21ee6e9b8f0a7a37439346422 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
@@ -376,6 +376,10 @@ class ListWrapper<E> extends ListBase<E> implements List<E> {
     elements.sort(compare);
   }
 
+  void shuffle() {
+    elements.shuffle();
+  }
+
   int indexOf(E element, [int start = 0]) {
     return elements.indexOf(element, start);
   }
@@ -583,4 +587,4 @@ class JavaPatternMatcher {
   String group(int i) => _match[i];
   int start() => _match.start;
   int end() => _match.end;
-}
+}