Add missing (and remove superfluous) 'explicit' from constructors.

chrome/browser/importer/firefox_importer_unittest_utils_mac.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 "chrome/browser/importer/firefox_importer_unittest_utils.h"
 
 #include "base/bind.h"
 #include "base/base_switches.h"
 #include "base/command_line.h"
 #include "base/file_path.h"
@@ skipping 251 matching lines @@
  private:
   NSSDecryptor decryptor_;
   IPC::Sender* sender_;
 };
 
 // Entry function in child process.
 MULTIPROCESS_IPC_TEST_MAIN(NSSDecrypterChildProcess) {
   MessageLoopForIO main_message_loop;
   FFDecryptorClientChannelListener listener;
 
-  IPC::Channel channel(kTestChannelID, IPC::Channel::MODE_CLIENT, &listener);
+  IPC::Channel channel(kTestChannelID,
+                       IPC::Channel::MODE_CLIENT, &listener);
   CHECK(channel.Connect());
   listener.SetSender(&channel);
 
   // run message loop
   MessageLoop::current()->Run();
 
   return 0;
 }