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

chrome/browser/extensions/api/socket/tcp_socket_unittest.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/extensions/api/socket/tcp_socket.h"
 
 #include "base/memory/scoped_ptr.h"
 #include "net/base/address_list.h"
 #include "net/base/completion_callback.h"
 #include "net/base/io_buffer.h"
@@ skipping 25 matching lines @@
   virtual bool IsConnected() const OVERRIDE {
     return true;
   }
 
  private:
   DISALLOW_COPY_AND_ASSIGN(MockTCPSocket);
 };
 
 class MockTCPServerSocket : public net::TCPServerSocket {
  public:
-  explicit MockTCPServerSocket()
+  MockTCPServerSocket()
       : net::TCPServerSocket(NULL, net::NetLog::Source()) {
   }
   MOCK_METHOD2(Listen, int(const net::IPEndPoint& address, int backlog));
   MOCK_METHOD2(Accept, int(scoped_ptr<net::StreamSocket>* socket,
                             const net::CompletionCallback& callback));
 
  private:
   DISALLOW_COPY_AND_ASSIGN(MockTCPServerSocket);
 };
 
@@ skipping 168 matching lines @@
   EXPECT_CALL(*tcp_server_socket, Listen(_, _)).Times(1);
   EXPECT_CALL(handler, OnAccept(_, _));
 
   std::string err_msg;
   EXPECT_EQ(net::OK, socket->Listen("127.0.0.1", 9999, 10, &err_msg));
   socket->Accept(base::Bind(&CompleteHandler::OnAccept,
         base::Unretained(&handler)));
 }
 
 }  // namespace extensions