MacViews: Remove constrained window dependencies for certificate viewer.

components/web_modal/web_contents_modal_dialog_views.cc

-// Copyright 2014 The Chromium Authors. All rights reserved.
+// Copyright 2016 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 "components/web_modal/web_contents_modal_dialog_manager.h"
 
 namespace web_modal {
 
 SingleWebContentsDialogManager*
-WebContentsModalDialogManager::CreateNativeWebModalManager(
+WebContentsModalDialogManager::CreateNativeWebModalOverlayManager(
     gfx::NativeWindow dialog,
     SingleWebContentsDialogManagerDelegate* native_delegate) {
-  // TODO(oshima): Investigate if we need to implement this.
   NOTREACHED();
-  return NULL;
+  return nullptr;
 }
 
 }  // namespace web_modal