[WebMIDI] Introduce MidiManagerUsb

media/midi/usb_midi_device.h

 // Copyright 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_USB_MIDI_DEVICE_H_
 #define MEDIA_MIDI_USB_MIDI_DEVICE_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/callback.h"
 #include "base/memory/scoped_vector.h"
 #include "media/base/media_export.h"
 
 namespace media {
 
+class UsbMidiDevice;
+
 class MEDIA_EXPORT UsbMidiDeviceDelegate {
  public:
   virtual ~UsbMidiDeviceDelegate() {}
-  virtual void ReceiveUsbMidiData(int endpoint_number,
+  virtual void ReceiveUsbMidiData(UsbMidiDevice* device,
+                                  int endpoint_number,
                                   const uint8* data,
                                   size_t size,
                                   double timestamp) = 0;
 };
 
 class MEDIA_EXPORT UsbMidiDevice {
  public:
   typedef ScopedVector<UsbMidiDevice> Devices;
   class Factory {
    public:
     typedef base::Callback<void(bool result, Devices* devices)> Callback;
     virtual ~Factory() {}
     // Enumerates devices.
     // Devices that have no USB-MIDI interfaces can be omitted.
     // When the operation succeeds, |callback| will be called with |true| and
     // devices.
     // Otherwise |callback| will be called with |false| and empty devices.
     // When this factory is destroyed during the operation, the operation
     // will be canceled silently (i.e. |callback| will not be called).
-    virtual void EnumerateDevices(Callback callback) = 0;
+    virtual void EnumerateDevices(UsbMidiDeviceDelegate* delegate,
+                                  Callback callback) = 0;
   };
 
   virtual ~UsbMidiDevice() {}
 
   // Returns the descriptor of this device.
   virtual std::vector<uint8> GetDescriptor() = 0;
 
   // Sends |data| to the given USB endpoint of this device.
   virtual void Send(int endpoint_number, const std::vector<uint8>& data) = 0;
 };
 
 }  // namespace media
 
 #endif  // MEDIA_MIDI_USB_MIDI_DEVICE_H_