Remove explicit keyword from multi-argument constructors

chrome/browser/chromeos/login/mock_authenticator.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_CHROMEOS_LOGIN_MOCK_AUTHENTICATOR_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_MOCK_AUTHENTICATOR_H_
 #pragma once
 
 #include <string>
 
@@ skipping 58 matching lines @@
 
  private:
   std::string expected_username_;
   std::string expected_password_;
 
   DISALLOW_COPY_AND_ASSIGN(MockAuthenticator);
 };
 
 class MockLoginUtils : public LoginUtils {
  public:
-  explicit MockLoginUtils(const std::string& expected_username,
-                          const std::string& expected_password);
+  MockLoginUtils(const std::string& expected_username,
+                 const std::string& expected_password);
   virtual ~MockLoginUtils();
 
   virtual bool ShouldWaitForWifi();
 
   virtual void PrepareProfile(const std::string& username,
                               const std::string& password,
                               const GaiaAuthConsumer::ClientLoginResult& res,
                               bool pending_requests,
                               Delegate* delegate);
 
@@ skipping 29 matching lines @@
   std::string expected_password_;
   std::string auth_token_;
   chromeos::BackgroundView* background_view_;
 
   DISALLOW_COPY_AND_ASSIGN(MockLoginUtils);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_MOCK_AUTHENTICATOR_H_