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

ash/common/system/tray/system_tray.cc

Index: ash/common/system/tray/system_tray.cc
diff --git a/ash/common/system/tray/system_tray.cc b/ash/common/system/tray/system_tray.cc
index 979e3a197bf51a66dbd25c7795bd57f0adfe2872..12e7a971b621e8ae5d61fd42de65ff3c784c3736 100644
--- a/ash/common/system/tray/system_tray.cc
+++ b/ash/common/system/tray/system_tray.cc
@@ -6,6 +6,7 @@
 
 #include "ash/common/ash_switches.h"
 #include "ash/common/login_status.h"
+#include "ash/common/material_design/material_design_controller.h"
 #include "ash/common/session/session_state_delegate.h"
 #include "ash/common/shelf/wm_shelf.h"
 #include "ash/common/shelf/wm_shelf_util.h"
@@ -20,6 +21,7 @@
 #include "ash/common/system/update/tray_update.h"
 #include "ash/common/system/user/tray_user.h"
 #include "ash/common/system/user/tray_user_separator.h"
+#include "ash/common/system/view_observer.h"
 #include "ash/common/system/web_notification/web_notification_tray.h"
 #include "ash/common/wm_lookup.h"
 #include "ash/common/wm_root_window_controller.h"
@@ -72,6 +74,9 @@ namespace ash {
 // The minimum width of the system tray menu width.
 const int kMinimumSystemTrayMenuWidth = 300;
 
+// Padding used to adjust the user-visible size of status tray dark background.
+const int kBackgroundTrayPadding = 3;
+
 // Class to initialize and manage the SystemTrayBubble and TrayBubbleWrapper
 // instances for a bubble.
 
@@ -121,8 +126,8 @@ class SystemBubbleWrapper {
 
 // SystemTray
 
-SystemTray::SystemTray(WmShelf* wm_shelf)
-    : TrayBackgroundView(wm_shelf),
+SystemTray::SystemTray(WmShelf* wm_shelf, ViewObserver* view_observer)
+    : TrayBackgroundView(wm_shelf, view_observer),
       web_notification_tray_(nullptr),
       detailed_item_(nullptr),
       default_bubble_height_(0),
@@ -153,6 +158,7 @@ void SystemTray::InitializeTrayItems(
   DCHECK(web_notification_tray);
   web_notification_tray_ = web_notification_tray;
   TrayBackgroundView::Initialize();
+  AdjustStatusTrayBackground();
   CreateItems(delegate);
 }
 
@@ -608,6 +614,9 @@ void SystemTray::SetShelfAlignment(ShelfAlignment alignment) {
   if (alignment == shelf_alignment())
     return;
   TrayBackgroundView::SetShelfAlignment(alignment);
+  if (!ash::MaterialDesignController::IsShelfMaterial()) {
+    AdjustStatusTrayBackground();
+  }
   UpdateAfterShelfAlignmentChange(alignment);
   // Destroy any existing bubble so that it is rebuilt correctly.
   CloseSystemBubbleAndDeactivateSystemTray();
@@ -775,4 +784,11 @@ void SystemTray::RecordSystemMenuMetrics() {
   }
 }
 
+void SystemTray::AdjustStatusTrayBackground() {
+  if (!ash::MaterialDesignController::IsShelfMaterial()) {
+    tray_container()->SetBorder(
+        views::Border::CreateEmptyBorder(gfx::Insets(kBackgroundTrayPadding)));
+  }
+}
+
 }  // namespace ash