Convert WindowOpenDisposition to an enum class.

chrome/browser/tab_contents/view_source_browsertest.cc

 // 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.
 
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/app/chrome_command_ids.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_commands.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "chrome/common/url_constants.h"
@@ skipping 150 matching lines @@
   // Switch back to the first tab and navigate it cross-process.
   browser()->tab_strip_model()->ActivateTabAt(0, true);
   ui_test_utils::NavigateToURL(browser(), GURL(chrome::kChromeUIVersionURL));
   EXPECT_TRUE(chrome::CanViewSource(browser()));
 
   // Navigate back in session history to ensure view-source mode is still
   // active.
   {
     ui_test_utils::UrlLoadObserver load_complete(
         url_viewsource, content::NotificationService::AllSources());
-    chrome::GoBack(browser(), CURRENT_TAB);
+    chrome::GoBack(browser(), WindowOpenDisposition::CURRENT_TAB);
     load_complete.Wait();
   }
 
   // Check whether the page is in view-source mode or not by checking if an
   // expected element on the page exists or not. In view-source mode it
   // should not be found.
   bool result = false;
   EXPECT_TRUE(content::ExecuteScriptAndExtractBool(
       browser()->tab_strip_model()->GetActiveWebContents(),
       "domAutomationController.send(document.getElementById('bar') === null);",
       &result));
   EXPECT_TRUE(result);
   EXPECT_FALSE(chrome::CanViewSource(browser()));
 }