Tech Debt Repayment for StartupBrowserCreatorImpl Refactor

chrome/browser/sessions/session_restore.h

 // 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.
 
 #ifndef CHROME_BROWSER_SESSIONS_SESSION_RESTORE_H_
 #define CHROME_BROWSER_SESSIONS_SESSION_RESTORE_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 10 matching lines @@
 
 namespace content {
 class WebContents;
 }
 
 // SessionRestore handles restoring either the last or saved session. Session
 // restore come in two variants, asynchronous or synchronous. The synchronous
 // variety is meant for startup and blocks until restore is complete.
 class SessionRestore {
  public:
-  enum Behavior {
+  // Bitmask representing behaviors available when restoring a session. Populate
+  // using the values below.
+  using BehaviorBitmask = uint32_t;
+
+  enum {
     // Indicates the active tab of the supplied browser should be closed.
     CLOBBER_CURRENT_TAB          = 1 << 0,
 
     // Indicates that if there is a problem restoring the last session then a
     // new tabbed browser should be created.
     ALWAYS_CREATE_TABBED_BROWSER = 1 << 1,
 
     // Restore blocks until complete. This is intended for use during startup
     // when we want to block until restore is complete.
     SYNCHRONOUS                  = 1 << 2,
   };
 
   // Notification callback list.
   using CallbackList = base::CallbackList<void(int)>;
 
   // Used by objects calling RegisterOnSessionRestoredCallback() to de-register
   // themselves when they are destroyed.
   using CallbackSubscription =
       std::unique_ptr<base::CallbackList<void(int)>::Subscription>;
 
   // Restores the last session. |behavior| is a bitmask of Behaviors, see it
   // for details. If |browser| is non-null the tabs for the first window are
   // added to it. Returns the last active browser.
   //
   // If |urls_to_open| is non-empty, a tab is added for each of the URLs.
   static Browser* RestoreSession(Profile* profile,
                                  Browser* browser,
-                                 uint32_t behavior,
+                                 BehaviorBitmask behavior,
                                  const std::vector<GURL>& urls_to_open);
 
   // Restores the last session when the last session crashed. It's a wrapper
   // of function RestoreSession.
   static void RestoreSessionAfterCrash(Browser* browser);
 
   // Opens the startup pages when the last session crashed.
   static void OpenStartupPagesAfterCrash(Browser* browser);
 
   // Specifically used in the restoration of a foreign session.  This function
@@ skipping 38 matching lines @@
     return on_session_restored_callbacks_;
   }
 
   // Contains all registered callbacks for session restore notifications.
   static CallbackList* on_session_restored_callbacks_;
 
   DISALLOW_COPY_AND_ASSIGN(SessionRestore);
 };
 
 #endif  // CHROME_BROWSER_SESSIONS_SESSION_RESTORE_H_