Add a factory function to create WebContentsView implementations.

content/browser/web_contents/web_contents_view_mac.mm

 // 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.
 
 #import <Carbon/Carbon.h>
 
 #import "content/browser/web_contents/web_contents_view_mac.h"
 
 #include <string>
 
@@ skipping 39 matching lines @@
 - (void)startDragWithDropData:(const WebDropData&)dropData
             dragOperationMask:(NSDragOperation)operationMask
                         image:(NSImage*)image
                        offset:(NSPoint)offset;
 - (void)cancelDeferredClose;
 - (void)clearWebContentsView;
 - (void)closeTabAfterEvent;
 - (void)viewDidBecomeFirstResponder:(NSNotification*)notification;
 @end
 
-namespace web_contents_view_mac {
-content::WebContentsView* CreateWebContentsView(
-    WebContentsImpl* web_contents,
-    content::WebContentsViewDelegate* delegate) {
+namespace content {
+WebContentsView* CreateWebContentsView(WebContentsImpl* web_contents,
+                                       WebContentsViewDelegate* delegate) {
   return new WebContentsViewMac(web_contents, delegate);
 }
 }
 
 WebContentsViewMac::WebContentsViewMac(
     WebContentsImpl* web_contents,
     content::WebContentsViewDelegate* delegate)
     : web_contents_(web_contents),
       delegate_(delegate) {
 }
@@ skipping 505 matching lines @@
       [[[notification userInfo] objectForKey:kSelectionDirection]
         unsignedIntegerValue];
   if (direction == NSDirectSelection)
     return;
 
   [self webContents]->
       FocusThroughTabTraversal(direction == NSSelectingPrevious);
 }
 
 @end