[Ash MD] Restore focus on detailed row when exiting detailed view

ash/common/system/tray/tray_details_view.cc

 // 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.
 
 #include "ash/common/system/tray/tray_details_view.h"
 
 #include "ash/common/material_design/material_design_controller.h"
 #include "ash/common/system/tray/fixed_sized_scroll_view.h"
 #include "ash/common/system/tray/system_tray.h"
 #include "ash/common/system/tray/system_tray_item.h"
@@ skipping 150 matching lines @@
   // TODO(tdanderson): Store login status as a member in TrayDetailsView
   // instead of its derived classes. Use this to perform an early return
   // if launching WebUI settings is not permitted, and provide a default
   // implementation to ShowSettings().
 }
 
 void TrayDetailsView::TransitionToDefaultView() {
   // Cache pointer to owner in this function scope. TrayDetailsView will be
   // deleted after called ShowDefaultView.
   SystemTrayItem* owner = owner_;
-  if (title_row_ && title_row_->content() && title_row_->content()->HasFocus())
-    owner->set_restore_focus(true);
+  if (MaterialDesignController::IsSystemTrayMenuMaterial()) {

[varkha, 2016/10/20 15:34:38]

Did you not merge this with the else if condition because when MDC will age out
of existence it would be easier to just remove the other condition? If so - I
agree that this is better even if it is not the shortest way to write this.

+    if (back_button_ && back_button_->HasFocus())
+      owner->set_restore_focus(true);
+  } else {
+    if (title_row_ && title_row_->content() &&
+        title_row_->content()->HasFocus()) {
+      owner->set_restore_focus(true);
+    }
+  }
   owner->system_tray()->ShowDefaultView(BUBBLE_USE_EXISTING);
   owner->set_restore_focus(false);
 }
 
 void TrayDetailsView::Layout() {
   if (bounds().IsEmpty()) {
     views::View::Layout();
     return;
   }
 
@@ skipping 26 matching lines @@
     if (index < child_count() - 1 && child_at(index + 1) != title_row_)
       scroll_border_->set_visible(true);
     else
       scroll_border_->set_visible(false);
   }
 
   views::View::OnPaintBorder(canvas);
 }
 
 }  // namespace ash