Fix object ownership in ui/base/models.

ui/views/controls/tree/tree_view.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_VIEWS_CONTROLS_TREE_TREE_VIEW_VIEWS_H_
 #define UI_VIEWS_CONTROLS_TREE_TREE_VIEW_VIEWS_H_
 
 #include <memory>
 #include <vector>
 
@@ skipping 318 matching lines @@
                                  int* node_depth);
 
   // Increments the selection. Invoked in response to up/down arrow.
   void IncrementSelection(IncrementType type);
 
   // If the current node is expanded, it's collapsed, otherwise selection is
   // moved to the parent.
   void CollapseOrSelectParent();
 
   // If the selected node is collapsed, it's expanded. Otherwise the first child
-  // is seleected.
+  // is selected.
   void ExpandOrSelectChild();
 
   // Implementation of Expand(). Returns true if at least one node was expanded
   // that previously wasn't.
   bool ExpandImpl(ui::TreeModelNode* model_node);
 
   PrefixSelector* GetPrefixSelector();
 
   // Returns whether |point| is in the bounds of |node|'s expand/collapse
   // control.
@@ skipping 55 matching lines @@
   int text_offset_;
 
   std::unique_ptr<PrefixSelector> selector_;
 
   DISALLOW_COPY_AND_ASSIGN(TreeView);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_CONTROLS_TREE_TREE_VIEW_VIEWS_H_