[MIDI] Make android MIDI port id unique

[MIDI] Make android MIDI port id unique

MIDI port id must be unique, as specified in the spec.

BUG=341423
Committed: https://crrev.com/b6cfa6a1c84229eab303875c9ea64f817338ff8e
Cr-Commit-Position: refs/heads/master@{#292553}

[yhirano, 2014-08-28 11:26:19]

yhirano@chromium.org changed reviewers:
+ toyoshim@chromium.org

[Takashi Toyoshima, 2014-08-28 11:52:11]

https://codereview.chromium.org/516893002/diff/20001/media/midi/midi_manager_...
File media/midi/midi_manager_usb.cc (right):

https://codereview.chromium.org/516893002/diff/20001/media/midi/midi_manager_...
media/midi/midi_manager_usb.cc:99: port.id = base::StringPrintf("port-%zu-%zu",
i, j);
I might be wrong, but the i and j mean the USB port location right?
I forget what is this, so maybe adding some comments here will be helpful:)

If it is easy to use USB PID/VID in addition to USB port location here? It is
not mandatory, but would be better.

[yhirano, 2014-08-28 13:09:14]

https://codereview.chromium.org/516893002/diff/20001/media/midi/midi_manager_...
File media/midi/midi_manager_usb.cc (right):

https://codereview.chromium.org/516893002/diff/20001/media/midi/midi_manager_...
media/midi/midi_manager_usb.cc:99: port.id = base::StringPrintf("port-%zu-%zu",
i, j);
On 2014/08/28 11:52:11, Takashi Toyoshima (chromium) wrote:
> I might be wrong, but the i and j mean the USB port location right?
> I forget what is this, so maybe adding some comments here will be helpful:)
> 
> If it is easy to use USB PID/VID in addition to USB port location here? It is
> not mandatory, but would be better.

They are just indices and are not meaningful. I will add PID/VID, but the USB
descriptor parser need to be fixed for it, so as a quirk I would propose this
CL.
Why I want to fix it now is, I am introducing MIDIInputMap and MIDIOutputMap.
Previously, duplicated IDs were no harm (while it violated the spec), but when
MIDIInputMap and MIDIOutMap are introduced duplicated IDs will be a serious
problem because they will be used as keys.

[Takashi Toyoshima, 2014-08-28 13:22:31]

Thank you for clarification and adding TODO.
Now it LGTM.

[yhirano, 2014-08-29 01:35:21]

The CQ bit was checked by yhirano@chromium.org

[commit-bot: I haz the power, 2014-08-29 01:36:13]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/yhirano@chromium.org/516893002/40001

[commit-bot: I haz the power, 2014-08-29 02:37:29]

Committed patchset #3 (id:40001) as 0b42ea7366cf483260f6fe330b663494302bd2d4

[commit-bot: I haz the power, 2014-09-10 03:05:29]

Patchset 3 (id:??) landed as
https://crrev.com/b6cfa6a1c84229eab303875c9ea64f817338ff8e
Cr-Commit-Position: refs/heads/master@{#292553}