Fix a couple issues with sticky headers

ash/common/system/tray/tray_popup_utils.h

 // Copyright 2016 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_TRAY_POPUP_UTILS_H_
 #define ASH_COMMON_SYSTEM_TRAY_TRAY_POPUP_UTILS_H_
 
 #include "ash/common/login_status.h"
 #include "ash/common/system/tray/tri_view.h"
 #include "base/strings/string16.h"
@@ skipping 67 matching lines @@
   // is used for all 'more' images as well as other images that appear in this
   // region, e.g. audio output icon.
   //
   // TODO(bruthig): Update all default rows to use this.
   static views::ImageView* CreateMoreImageView();
 
   // Returns a slider configured for proper layout within a TriView container
   // with a FillLayout.
   static views::Slider* CreateSlider(views::SliderListener* listener);
 
+  // Sets up |view| to be a sticky header in a tray detail scroll view.
+  static void ConfigureAsStickyHeader(views::View* view);
+
   // Configures |container_view| just like CreateDefaultRowView() would
   // configure |container| on its returned TriView. To be used when mutliple
   // targetable areas are required within a single row.
   static void ConfigureContainer(TriView::Container container,
                                  views::View* container_view);
 
   // Creates a button for use in the system menu that only has a visible border
   // when being hovered/clicked. Caller assumes ownership.
   static views::LabelButton* CreateTrayPopupBorderlessButton(
       views::ButtonListener* listener,
@@ skipping 33 matching lines @@
 
   // Returns the default border used by CreateDefaultRow() and
   // ConfigureContainer() for the given |container|.
   static std::unique_ptr<views::Border> CreateDefaultBorder(
       TriView::Container container);
 };
 
 }  // namespace ash
 
 #endif  // ASH_COMMON_SYSTEM_TRAY_TRAY_POPUP_UTILS_H_