Remove explicit keyword from multi-argument constructors

jingle/notifier/listener/push_notifications_listen_task.h

 // Copyright (c) 2010 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.
 //
 // This class listens for notifications from the Google Push notifications
 // service, and signals when they arrive.  It checks all incoming stanzas to
 // see if they look like notifications, and filters out those which are not
 // valid.
 //
 // The task is deleted automatically by the buzz::XmppClient. This occurs in the
@@ skipping 14 matching lines @@
 
 class PushNotificationsListenTask : public buzz::XmppTask {
  public:
   class Delegate {
    public:
      virtual ~Delegate() {}
      virtual void OnNotificationReceived(
         const Notification& notification) = 0;
   };
 
-  explicit PushNotificationsListenTask(Task* parent, Delegate* delegate);
+  PushNotificationsListenTask(Task* parent, Delegate* delegate);
   virtual ~PushNotificationsListenTask();
 
   // Overriden from buzz::XmppTask.
   virtual int ProcessStart();
   virtual int ProcessResponse();
   virtual bool HandleStanza(const buzz::XmlElement* stanza);
 
  private:
   bool IsValidNotification(const buzz::XmlElement* stanza);
 
   Delegate* delegate_;
 
   DISALLOW_COPY_AND_ASSIGN(PushNotificationsListenTask);
 };
 
 typedef PushNotificationsListenTask::Delegate
     PushNotificationsListenTaskDelegate;
 
 }  // namespace notifier
 
 #endif  // JINGLE_NOTIFIER_PUSH_NOTIFICATIONS_LISTENER_LISTEN_TASK_H_