Deprecate LinkedList.

sdk/lib/collection/queue.dart

Index: sdk/lib/collection/queue.dart
diff --git a/sdk/lib/collection/queue.dart b/sdk/lib/collection/queue.dart
index 7eb77d448feddeda9fc26b72ef0988962ad44384..d62e49497ec3ffd4a02eb414fa1ffc6d89212fad 100644
--- a/sdk/lib/collection/queue.dart
+++ b/sdk/lib/collection/queue.dart
@@ -117,6 +117,7 @@ class _DoubleLink<Link extends _DoubleLink<Link>> {
  * An entry in a doubly linked list. It contains a pointer to the next
  * entry, the previous entry, and the boxed element.
  */
+@deprecated
 class DoubleLinkedQueueEntry<E> extends _DoubleLink<DoubleLinkedQueueEntry<E>> {
   /// The element in the queue.
   E element;
@@ -252,8 +253,12 @@ class _DoubleLinkedQueueSentinel<E> extends _DoubleLinkedQueueEntry<E> {
 /**
  * A [Queue] implementation based on a double-linked list.
  *
+ * Deprecated. Use [ListQueue] or `DoubleLinkedQueue` from package
+ * `collection`, instead. [https://pub.dartlang.org/packages/collection]
+ *
  * Allows constant time add, remove-at-ends and peek operations.
  */
+@deprecated
 class DoubleLinkedQueue<E> extends Iterable<E> implements Queue<E> {
   _DoubleLinkedQueueSentinel<E> _sentinel;
   int _elementCount = 0;