Fix bug in internal SplayTreeIterator constructor.

sdk/lib/collection/splay_tree.dart

Index: sdk/lib/collection/splay_tree.dart
diff --git a/sdk/lib/collection/splay_tree.dart b/sdk/lib/collection/splay_tree.dart
index 12cfac36441b38a4d0579e31760eba8f181b42cb..4674f8c27c3bee32872ce8247044d723601088ce 100644
--- a/sdk/lib/collection/splay_tree.dart
+++ b/sdk/lib/collection/splay_tree.dart
@@ -525,7 +525,12 @@ abstract class _SplayTreeIterator<T> implements Iterator<T> {
         _modificationCount = tree._modificationCount {
     int compare = tree._splay(startKey);
     _splayCount = tree._splayCount;
-    _findLeftMostDescendent(compare < 0 ? tree._root.right : tree._root);
+    if (compare < 0) {
+      // Don't include the root, start at the next element after the root.
+      _findLeftMostDescendent(tree._root.right);
+    } else {
+      _workList.add(tree._root);
+    }
   }
 
   T get current {
@@ -533,10 +538,6 @@ abstract class _SplayTreeIterator<T> implements Iterator<T> {
     return _getValue(_currentNode);
   }
 
-  _SplayTreeNode _findStartNode(T key) {
-
-  }
-
   void _findLeftMostDescendent(_SplayTreeNode node) {
     while (node != null) {
       _workList.add(node);