Fix a memory leak in MidiManagerAlsa initialization.

media/midi/midi_manager_alsa.cc

 // Copyright 2014 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 "media/midi/midi_manager_alsa.h"
 
 #include <alsa/asoundlib.h>
 #include <stdlib.h>
 #include <algorithm>
 #include <string>
@@ skipping 166 matching lines @@
       const std::string card_name = snd_ctl_card_info_get_longname(card);
       size_t at_index = card_name.rfind(" at ");
       if (std::string::npos != at_index) {
         size_t name_index = card_name.rfind(name, at_index - 1);
         if (std::string::npos != name_index)
           manufacturer = card_name.substr(0, name_index - 1);
       }
       const std::string driver = snd_ctl_card_info_get_driver(card);
       cards.push_back(new CardInfo(name, manufacturer, driver));
     }
+    snd_ctl_close(handle);
   }
 
   // Enumerate all ports in all clients.
   snd_seq_client_info_t* client_info;
   snd_seq_client_info_alloca(&client_info);
   snd_seq_port_info_t* port_info;
   snd_seq_port_info_alloca(&port_info);
 
   snd_seq_client_info_set_client(client_info, -1);
   // Enumerate clients.
@@ skipping 246 matching lines @@
   event_thread_.message_loop()->PostTask(
       FROM_HERE,
       base::Bind(&MidiManagerAlsa::EventLoop, base::Unretained(this)));
 }
 
 MidiManager* MidiManager::Create() {
   return new MidiManagerAlsa();
 }
 
 }  // namespace media