[rAc OSX] Factor out AutofillHeader class to contain dialog header elements.

chrome/browser/ui/cocoa/autofill/autofill_dialog_cocoa.mm

 // Copyright (c) 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 "chrome/browser/ui/cocoa/autofill/autofill_dialog_cocoa.h"
 
 #include "base/bind.h"
 #include "base/mac/scoped_nsobject.h"
 #include "base/message_loop/message_loop.h"
 #include "base/strings/sys_string_conversions.h"
@@ skipping 19 matching lines @@
   // Cancel potential relayout requests, since the AutofillDialogController
   // is about to go away, but relayout requests assume it will still exist.
   [sheet_delegate_ cancelRelayout];
 }
 
 void AutofillDialogCocoa::Show() {
   // This should only be called once.
   DCHECK(!sheet_delegate_.get());
   sheet_delegate_.reset([[AutofillDialogWindowController alloc]
        initWithWebContents:delegate_->GetWebContents()
-            autofillDialog:this]);
+                    dialog:this]);
   base::scoped_nsobject<CustomConstrainedWindowSheet> sheet(
       [[CustomConstrainedWindowSheet alloc]
           initWithCustomWindow:[sheet_delegate_ window]]);
   constrained_window_.reset(
       new ConstrainedWindowMac(this, delegate_->GetWebContents(), sheet));
   [sheet_delegate_ show];
 }
 
 void AutofillDialogCocoa::Hide() {
   [sheet_delegate_ hide];
@@ skipping 147 matching lines @@
 }
 
 void AutofillDialogCocoa::OnConstrainedWindowClosed(
     ConstrainedWindowMac* window) {
   constrained_window_.reset();
   // |this| belongs to |delegate_|, so no self-destruction here.
   delegate_->ViewClosed();
 }
 
 }  // autofill