Convert WindowOpenDisposition to an enum class.

chrome/browser/chromeos/attestation/platform_verification_dialog.cc

 // 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 "chrome/browser/chromeos/attestation/platform_verification_dialog.h"
 
 #include <stddef.h>
 
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/profiles/profile.h"
@@ skipping 125 matching lines @@
   Browser* browser = chrome::FindBrowserWithWebContents(web_contents());
   const GURL learn_more_url(chrome::kEnhancedPlaybackNotificationLearnMoreURL);
 
   // |web_contents()| might not be in a browser in case of v2 apps. In that
   // case, open a new tab in the usual way.
   if (!browser) {
     Profile* profile =
         Profile::FromBrowserContext(web_contents()->GetBrowserContext());
     chrome::NavigateParams params(
         profile, learn_more_url, ui::PAGE_TRANSITION_LINK);
-    params.disposition = SINGLETON_TAB;
+    params.disposition = WindowOpenDisposition::SINGLETON_TAB;
     chrome::Navigate(&params);
   } else {
     chrome::ShowSingletonTab(browser, learn_more_url);
   }
 }
 
 void PlatformVerificationDialog::DidStartNavigationToPendingEntry(
     const GURL& url,
     content::NavigationController::ReloadType reload_type) {
   views::Widget* widget = GetWidget();
   if (widget)
     widget->Close();
 }
 
 }  // namespace attestation
 }  // namespace chromeos