ash: fix multiple stack-use-after-scope issues with GetPrimaryDisplay use.

ash/content/keyboard_overlay/keyboard_overlay_delegate.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/content/keyboard_overlay/keyboard_overlay_delegate.h"
 
 #include <algorithm>
 
 #include "ash/shell.h"
 #include "base/bind.h"
@@ skipping 60 matching lines @@
   widget_ = new views::Widget;
   views::Widget::InitParams params(
       views::Widget::InitParams::TYPE_WINDOW_FRAMELESS);
   params.context = Shell::GetPrimaryRootWindow();
   params.delegate = view;
   widget_->Init(params);
 
   // Show the widget at the bottom of the work area.
   gfx::Size size;
   GetDialogSize(&size);
-  const gfx::Rect& rect =
-      display::Screen::GetScreen()
-          ->GetDisplayNearestWindow(widget_->GetNativeView())
-          .work_area();
+  const gfx::Rect rect = display::Screen::GetScreen()
+                             ->GetDisplayNearestWindow(widget_->GetNativeView())
+                             .work_area();
   gfx::Rect bounds(rect.x() + (rect.width() - size.width()) / 2,
                    rect.y() + (rect.height() - size.height()) / 2, size.width(),
                    size.height());
   widget_->SetBounds(bounds);
 
   // The widget will be shown when the web contents gets ready to display.
   return widget_;
 }
 
 ui::ModalType KeyboardOverlayDelegate::GetDialogModalType() const {
@@ skipping 39 matching lines @@
 bool KeyboardOverlayDelegate::ShouldShowDialogTitle() const {
   return false;
 }
 
 bool KeyboardOverlayDelegate::HandleContextMenu(
     const content::ContextMenuParams& params) {
   return true;
 }
 
 }  // namespace ash