Remove Collection, Collections and clean up List/Set/Queue implementations of retain/remove.

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 c5d5d367ea67d876ce5f4aed0af2a3eb1d9e3c8e..85947d096b6b06304acac5e196f5a6071d2ee815 100644
--- a/sdk/lib/collection/queue.dart
+++ b/sdk/lib/collection/queue.dart
@@ -9,7 +9,7 @@ part of dart.collection;
  * can iterate over the elements of a queue through [forEach] or with
  * an [Iterator].
  */
-abstract class Queue<E> implements Collection<E> {
+abstract class Queue<E> implements Iterable<E> {
 
   /**
    * Creates a queue.
@@ -160,7 +160,7 @@ class _DoubleLinkedQueueEntrySentinel<E> extends DoubleLinkedQueueEntry<E> {
  *
  * Can do [removeAll] and [retainAll] in linear time.
  */
-class DoubleLinkedQueue<E> extends Collection<E> implements Queue<E> {
+class DoubleLinkedQueue<E> extends Iterable<E> implements Queue<E> {
   _DoubleLinkedQueueEntrySentinel<E> _sentinel;
   int _elementCount = 0;
 
@@ -310,7 +310,7 @@ class DoubleLinkedQueue<E> extends Collection<E> implements Queue<E> {
   }
 
   String toString() {
-    return Collections.collectionToString(this);
+    return ToString.iterableToString(this);
   }
 }
 
@@ -351,10 +351,10 @@ class _DoubleLinkedQueueIterator<E> implements Iterator<E> {
  *
  * The structure is efficient for any queue or stack usage.
  *
- * Collection operations like [removeAll] and [removeWhere] are very
+ * Operations like [removeAll] and [removeWhere] are very
  * inefficient. If those are needed, use a [DoubleLinkedQueue] instead.
  */
-class ListQueue<E> extends Collection<E> implements Queue<E>{
+class ListQueue<E> extends Iterable<E> implements Queue<E>{
   static const int _INITIAL_CAPACITY = 8;
   List<E> _table;
   int _head;
@@ -490,14 +490,6 @@ class ListQueue<E> extends Collection<E> implements Queue<E>{
     _modificationCount++;
   }
 
-  void removeAll(Iterable objectsToRemove) {
-    IterableMixinWorkaround.removeAllList(this, objectsToRemove);
-  }
-
-  void retainAll(Iterable objectsToRetain) {
-    IterableMixinWorkaround.retainAll(this, objectsToRetain);
-  }
-
   void _filterWhere(bool test(E element), bool removeMatching) {
     int index = _head;
     int modificationCount = _modificationCount;
@@ -546,7 +538,7 @@ class ListQueue<E> extends Collection<E> implements Queue<E>{
   }
 
   String toString() {
-    return Collections.collectionToString(this);
+    return ToString.iterableToString(this);
   }
 
   // Queue interface.