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

ash/common/system/tray/system_tray.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 ASH_COMMON_SYSTEM_TRAY_SYSTEM_TRAY_H_
 #define ASH_COMMON_SYSTEM_TRAY_SYSTEM_TRAY_H_
 
 #include <map>
 #include <memory>
 #include <vector>
@@ skipping 11 matching lines @@
 enum class LoginStatus;
 class ScreenTrayItem;
 class SystemBubbleWrapper;
 class SystemTrayDelegate;
 class SystemTrayItem;
 class TrayAccessibility;
 class TrayCast;
 class TrayDate;
 class TrayUpdate;
 class TrayUser;
+class ViewObserver;
 class WebNotificationTray;
 
 // There are different methods for creating bubble views.
 enum BubbleCreationType {
   BUBBLE_CREATE_NEW,    // Closes any existing bubble and creates a new one.
   BUBBLE_USE_EXISTING,  // Uses any existing bubble, or creates a new one.
 };
 
 class ASH_EXPORT SystemTray : public TrayBackgroundView,
                               public views::TrayBubbleView::Delegate {
  public:
-  explicit SystemTray(WmShelf* wm_shelf);
+  explicit SystemTray(WmShelf* wm_shelf, ViewObserver* view_observer);
   ~SystemTray() override;
 
   // Calls TrayBackgroundView::Initialize(), creates the tray items, and
   // adds them to SystemTrayNotifier.
   void InitializeTrayItems(SystemTrayDelegate* delegate,
                            WebNotificationTray* web_notification_tray);
 
   // Resets internal pointers.
   void Shutdown();
 
@@ skipping 151 matching lines @@
 
   // Deactivate the system tray in the shelf if it was active before.
   void CloseSystemBubbleAndDeactivateSystemTray();
 
   // Records UMA metrics for the number of user-visible rows in the system menu
   // and the percentage of the work area height covered by the system menu.
   void RecordSystemMenuMetrics();
 
   const ScopedVector<SystemTrayItem>& items() const { return items_; }
 
+  // Sets an empty border around the system tray to change user-visible size
+  // of the dark background. Doesn't do anything in MD.
+  void AdjustStatusTrayBackground();
+
   // Overridden from ActionableView.
   bool PerformAction(const ui::Event& event) override;
 
   // The web notification tray view that appears adjacent to this view.
   WebNotificationTray* web_notification_tray_;
 
   // Owned items.
   ScopedVector<SystemTrayItem> items_;
 
   // Pointers to members of |items_|.
@@ skipping 30 matching lines @@
   // A reference to the Screen share and capture item.
   ScreenTrayItem* screen_capture_tray_item_;  // not owned
   ScreenTrayItem* screen_share_tray_item_;    // not owned
 
   DISALLOW_COPY_AND_ASSIGN(SystemTray);
 };
 
 }  // namespace ash
 
 #endif  // ASH_COMMON_SYSTEM_TRAY_SYSTEM_TRAY_H_