Fix sizing of tray details scroll views.

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/ash_view_ids.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"
@@ skipping 368 matching lines @@
 }
 
 void TrayDetailsView::Layout() {
   if (bounds().IsEmpty()) {
     views::View::Layout();
     return;
   }
 
   if (scroller_) {
     if (UseMd()) {
-      gfx::Size scroller_size = scroll_content_->GetPreferredSize();
+      gfx::Size scroller_size = scroller()->GetPreferredSize();
       gfx::Size pref_size = GetPreferredSize();
       scroller()->ClipHeightTo(
           0, scroller_size.height() - (pref_size.height() - height()));
     } else {
       scroller_->set_fixed_size(gfx::Size());
       gfx::Size size = GetPreferredSize();
 
       // Set the scroller to fill the space above the bottom row, so that the
       // bottom row of the detailed view will always stay just above the title
       // row.
@@ skipping 20 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