mac: Update clients of scoped_nsobject.h.

ui/base/cocoa/controls/hover_image_menu_button_cell.mm

 // Copyright 2013 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.
 
 #import "ui/base/cocoa/controls/hover_image_menu_button_cell.h"
 
 @implementation HoverImageMenuButtonCell
 
 @synthesize hovered = hovered_;
 
@@ skipping 33 matching lines @@
 
   if ([self isHovered] && [self hoverImage])
     return [self hoverImage];
 
   // Note that NSPopUpButtonCell updates the cell image when the [self menuItem]
   // changes.
   return [self image];
 }
 
 - (void)setDefaultImage:(NSImage*)defaultImage {
-  scoped_nsobject<NSMenuItem> buttonMenuItem([[NSMenuItem alloc] init]);
+  base::scoped_nsobject<NSMenuItem> buttonMenuItem([[NSMenuItem alloc] init]);
   [buttonMenuItem setImage:defaultImage];
   [self setMenuItem:buttonMenuItem];
 }
 
 - (void)drawWithFrame:(NSRect)cellFrame
                inView:(NSView*)controlView {
   [[self imageToDraw] drawInRect:cellFrame
                         fromRect:NSZeroRect
                        operation:NSCompositeSourceOver
                         fraction:1.0
                   respectFlipped:YES
                            hints:nil];
 }
 
 @end