Enable WebMIDI for Windows behind the flag

media/midi/midi_manager_win.h

Index: media/midi/midi_manager_win.h
diff --git a/media/midi/midi_manager_win.h b/media/midi/midi_manager_win.h
new file mode 100644
index 0000000000000000000000000000000000000000..d4160fab6a9cd43367541eda5e8ad4647662e375
--- /dev/null
+++ b/media/midi/midi_manager_win.h
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+// Copyright (c) 2013 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 MEDIA_MIDI_MIDI_MANAGER_WIN_H_
+#define MEDIA_MIDI_MIDI_MANAGER_WIN_H_
+
+#include <vector>
+
+#include "base/basictypes.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/threading/thread.h"
+#include "media/midi/midi_manager.h"
+
+namespace media {
+
+class MIDIManagerWin : public MIDIManager {
+ public:
+  MIDIManagerWin();
+  virtual ~MIDIManagerWin();
+
+  // MIDIManager implementation.
+  virtual bool Initialize() OVERRIDE;
+  virtual void DispatchSendMIDIData(MIDIManagerClient* client,
+                                    uint32 port_index,
+                                    const std::vector<uint8>& data,
+                                    double timestamp) OVERRIDE;
+
+ private:
+  class InDeviceInfo;
+  class OutDeviceInfo;
+  std::vector<scoped_ptr<InDeviceInfo> > in_devices_;
+  std::vector<scoped_ptr<OutDeviceInfo> > out_devices_;
+  base::Thread send_thread_;
+  DISALLOW_COPY_AND_ASSIGN(MIDIManagerWin);
+};
+
+}  // namespace media
+
+#endif  // MEDIA_MIDI_MIDI_MANAGER_WIN_H_