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

ash/common/system/overview/overview_button_tray.cc

 // 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.
 
 #include "ash/common/system/overview/overview_button_tray.h"
 
 #include "ash/common/material_design/material_design_controller.h"
 #include "ash/common/session/session_state_delegate.h"
 #include "ash/common/shelf/shelf_constants.h"
 #include "ash/common/shelf/shelf_types.h"
@@ skipping 105 matching lines @@
 void OverviewButtonTray::SetIconBorderForShelfAlignment() {
   if (ash::MaterialDesignController::IsShelfMaterial()) {
     // Pad button size to align with other controls in the system tray.
     const gfx::ImageSkia image = icon_->GetImage();
     const int vertical_padding = (kTrayItemSize - image.height()) / 2;
     const int horizontal_padding = (kTrayItemSize - image.width()) / 2;
     icon_->SetBorder(views::Border::CreateEmptyBorder(
         gfx::Insets(vertical_padding, horizontal_padding)));
   } else {
     if (IsHorizontalAlignment(shelf_alignment())) {
-      icon_->SetBorder(views::Border::CreateEmptyBorder(
-          kHorizontalShelfVerticalPadding, kHorizontalShelfHorizontalPadding,
-          kHorizontalShelfVerticalPadding, kHorizontalShelfHorizontalPadding));
+      icon_->SetBorder(views::Border::CreateEmptyBorder(gfx::Insets(
+          kHorizontalShelfVerticalPadding, kHorizontalShelfHorizontalPadding)));
     } else {
-      icon_->SetBorder(views::Border::CreateEmptyBorder(
-          kVerticalShelfVerticalPadding, kVerticalShelfHorizontalPadding,
-          kVerticalShelfVerticalPadding, kVerticalShelfHorizontalPadding));
+      icon_->SetBorder(views::Border::CreateEmptyBorder(gfx::Insets(
+          kVerticalShelfVerticalPadding, kVerticalShelfHorizontalPadding)));

[varkha, 2016/08/19 16:33:39]

nit: Can you calculate insets in all 3 cases and then
icon_->SetBorder(views::Border::CreateEmptyBorder(insets)) only once?

[yiyix, 2016/08/19 19:07:55]

Done.

     }
   }
 }
 
 void OverviewButtonTray::UpdateIconVisibility() {
   // The visibility of the OverviewButtonTray has diverge from
   // WindowSelectorController::CanSelect. The visibility of the button should
   // not change during transient times in which CanSelect is false. Such as when
   // a modal dialog is present.
   WmShell* shell = WmShell::Get();
   SessionStateDelegate* session_state_delegate =
       shell->GetSessionStateDelegate();
 
   SetVisible(
       shell->maximize_mode_controller()->IsMaximizeModeWindowManagerEnabled() &&
       session_state_delegate->IsActiveUserSessionStarted() &&
       !session_state_delegate->IsScreenLocked() &&
       session_state_delegate->GetSessionState() ==
           SessionStateDelegate::SESSION_STATE_ACTIVE &&
       shell->system_tray_delegate()->GetUserLoginStatus() !=
           LoginStatus::KIOSK_APP);
 }
 
 }  // namespace ash