[Payments] Add combobox support to editors.

ui/views/controls/combobox/combobox.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_COMBOBOX_COMBOBOX_H_
 #define UI_VIEWS_CONTROLS_COMBOBOX_COMBOBOX_H_
 
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "base/strings/string16.h"
 #include "base/time/time.h"
+#include "ui/base/models/combobox_model.h"
 #include "ui/views/controls/button/button.h"
 #include "ui/views/controls/prefix_delegate.h"
 
 namespace gfx {
 class FontList;
 }
 
 namespace ui {
-class ComboboxModel;
 class MenuModel;
 }
 
 namespace views {
 namespace test {
 class ComboboxTestApi;
 }
 
 class ComboboxListener;
 class CustomButton;
@@ skipping 18 matching lines @@
  public:
   // The style of the combobox.
   enum Style {
     STYLE_NORMAL,
     STYLE_ACTION,
   };
 
   // The combobox's class name.
   static const char kViewClassName[];
 
-  // |model| is not owned by the combobox.
+  // |model| is owned by the combobox when using this constructor.
+  explicit Combobox(std::unique_ptr<ui::ComboboxModel> model,
+                    Style style = STYLE_NORMAL);
+  // |model| is not owned by the combobox when using this constructor.
   explicit Combobox(ui::ComboboxModel* model, Style style = STYLE_NORMAL);
   ~Combobox() override;
 
   static const gfx::FontList& GetFontList();
 
   // Sets the listener which will be called when a selection has been made.
   void set_listener(ComboboxListener* listener) { listener_ = listener; }
 
   // Informs the combobox that its model changed.
   void ModelChanged();
@@ skipping 82 matching lines @@
   gfx::Size GetContentSize() const;
 
   // Handles the clicking event.
   void HandleClickEvent();
 
   PrefixSelector* GetPrefixSelector();
 
   // Returns the width of the combobox's arrow container.
   int GetArrowContainerWidth() const;
 
-  // Our model. Not owned.
+  // Optionally used to tie the lifetime of the model to this combobox. See
+  // constructor.
+  std::unique_ptr<ui::ComboboxModel> owned_model_;
+
+  // Reference to our model, which may be owned or not.
   ui::ComboboxModel* model_;
 
   // The visual style of this combobox.
   const Style style_;
 
   // Our listener. Not owned. Notified when the selected index change.
   ComboboxListener* listener_;
 
   // The current selected index; -1 and means no selection.
   int selected_index_;
@@ skipping 51 matching lines @@
 
   // Used for making calbacks.
   base::WeakPtrFactory<Combobox> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(Combobox);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_CONTROLS_COMBOBOX_COMBOBOX_H_