[Chrome OS MD] Draw a 1px separator between 2 tray items

ash/common/system/chromeos/virtual_keyboard/virtual_keyboard_tray.h

 // Copyright 2014 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 ASH_COMMON_SYSTEM_CHROMEOS_VIRTUAL_KEYBOARD_VIRTUAL_KEYBOARD_TRAY_H_
 #define ASH_COMMON_SYSTEM_CHROMEOS_VIRTUAL_KEYBOARD_VIRTUAL_KEYBOARD_TRAY_H_
 
 #include "ash/common/keyboard/keyboard_ui_observer.h"
 #include "ash/common/system/tray/tray_background_view.h"
 #include "base/macros.h"
 #include "ui/views/controls/button/button.h"
 
 namespace views {
 class ImageButton;
 }
 
 namespace ash {
+class LogoutButtonTray;
+}
+
+namespace ash {

[varkha, 2016/07/14 21:34:47]

Don't need it second time.

[yiyix, 2016/07/26 20:27:30]

Done.

 
 // TODO(sky): make this visible on non-chromeos platforms.
 class VirtualKeyboardTray : public TrayBackgroundView,
                             public views::ButtonListener,
                             public KeyboardUIObserver {
  public:
   explicit VirtualKeyboardTray(WmShelf* wm_shelf);
   ~VirtualKeyboardTray() override;
 
+  // Resets internal pointers.
+  void Shutdown();
+
+  // Calls TrayBackgroundView::Initialize() and save a pointer to logout_button.

[varkha, 2016/07/14 21:34:47]

nit: How about
// Sets |logout_button_tray_| to |logout_button_tray| and calls
TrayBackgroundView::Initialize().

[yiyix, 2016/07/26 20:27:30]

As we are using the new approach. we don't need to modify the initialize method.

+  void InitializeTrayItems(LogoutButtonTray* logout_button_tray);

[varkha, 2016/07/14 21:34:47]

Hmm. Not sure if you need this method. Maybe simply add a
set_logout_button_tray() and call it where you would normally call Initialize
(before or after because as far as I can tell OnPaint() won't get called until
later).

[yiyix, 2016/07/26 20:27:30]

Per our discussion offline, I will use observer design pattern to avoid that one
tray knows about another tray.

+
   // TrayBackgroundView:
   void SetShelfAlignment(ShelfAlignment alignment) override;
   base::string16 GetAccessibleNameForTray() override;
   void HideBubbleWithView(const views::TrayBubbleView* bubble_view) override;
   void ClickedOutsideBubble() override;
   bool PerformAction(const ui::Event& event) override;
 
   // views::ButtonListener:
   void ButtonPressed(views::Button* sender, const ui::Event& event) override;
 
   // KeyboardUIObserver:
   void OnKeyboardEnabledStateChanged(bool new_value) override;
 
  private:
+  // views::View:
+  void OnPaint(gfx::Canvas* canvas) override;
+
   views::ImageButton* button_;  // Not owned.
+  LogoutButtonTray* logout_button_tray_;  // Not owned.
 
   DISALLOW_COPY_AND_ASSIGN(VirtualKeyboardTray);
 };
 
 }  // namespace ash
 
 #endif  // ASH_COMMON_SYSTEM_CHROMEOS_VIRTUAL_KEYBOARD_VIRTUAL_KEYBOARD_TRAY_H_