Make callers of CommandLine use it via the base:: namespace.

content/shell/browser/shell_web_contents_view_delegate_mac.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.
 
 #include "content/shell/browser/shell_web_contents_view_delegate.h"
 
 #import  <Cocoa/Cocoa.h>
 
 #include "base/command_line.h"
 #include "content/public/browser/render_frame_host.h"
@@ skipping 77 matching lines @@
     WebContents* web_contents)
     : web_contents_(web_contents) {
 }
 
 ShellWebContentsViewDelegate::~ShellWebContentsViewDelegate() {
 }
 
 void ShellWebContentsViewDelegate::ShowContextMenu(
     RenderFrameHost* render_frame_host,
     const ContextMenuParams& params) {
-  if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kDumpRenderTree))
+  if (base::CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kDumpRenderTree))
     return;
 
   params_ = params;
   bool has_link = !params_.unfiltered_link_url.is_empty();
   bool has_selection = ! params_.selection_text.empty();
 
   NSMenu* menu = [[[NSMenu alloc] initWithTitle:@""] autorelease];
   ShellContextMenuDelegate* delegate =
       [[ShellContextMenuDelegate alloc] initWithDelegate:this];
   [menu setDelegate:delegate];
@@ skipping 149 matching lines @@
       break;
     }
     case ShellContextMenuItemInspectTag: {
       ShellDevToolsFrontend::Show(web_contents_);
       break;
     }
   }
 }
 
 }  // namespace content