Remove explicit keyword from multi-argument constructors

chrome/browser/sessions/tab_restore_service.h

 // Copyright (c) 2011 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_TAB_RESTORE_SERVICE_H_
 #define CHROME_BROWSER_SESSIONS_TAB_RESTORE_SERVICE_H_
 #pragma once
 
 #include <list>
 #include <set>
@@ skipping 99 matching lines @@
 
     // Index of the selected tab.
     int selected_tab_index;
   };
 
   typedef std::list<Entry*> Entries;
 
   // Creates a new TabRestoreService and provides an object that provides the
   // current time. The TabRestoreService does not take ownership of the
   // |time_factory_|.
-  explicit TabRestoreService(Profile* profile,
-                             TimeFactory* time_factory_ = NULL);
+  TabRestoreService(Profile* profile, TimeFactory* time_factory_ = NULL);
 
   virtual ~TabRestoreService();
 
   // Adds/removes an observer. TabRestoreService does not take ownership of
   // the observer.
   void AddObserver(TabRestoreServiceObserver* observer);
   void RemoveObserver(TabRestoreServiceObserver* observer);
 
   // Creates a Tab to represent |tab| and notifies observers the list of
   // entries has changed.
@@ skipping 206 matching lines @@
   // loading LoadStateChanged is invoked, which adds these entries to
   // entries_.
   std::vector<Entry*> staging_entries_;
 
   TimeFactory* time_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(TabRestoreService);
 };
 
 #endif  // CHROME_BROWSER_SESSIONS_TAB_RESTORE_SERVICE_H_