Web MIDI (Linux): Improve id quality, create opaque id, prep for hotplug

Improve id quality, create opaque id, prep for hotplug

BUG=466721, 431489
Committed: https://crrev.com/eaea4405a27a01da0de837b09b542f54a31d5d00
Cr-Commit-Position: refs/heads/master@{#321412}

[Adam Goode, 2015-03-19 11:57:33]

agoode@chromium.org changed reviewers:
+ agl@chromium.org, toyoshim@chromium.org, wolenetz@chromium.org

[Adam Goode, 2015-03-19 11:57:34]

wolenetz for media/DEPS
agl for crypto/DEPS
toyoshim for media/midi

[agl, 2015-03-19 12:05:18]

LGTM

https://codereview.chromium.org/1020783002/diff/40001/media/midi/midi_manager...
File media/midi/midi_manager_alsa.cc (right):

https://codereview.chromium.org/1020783002/diff/40001/media/midi/midi_manager...
media/midi/midi_manager_alsa.cc:433: crypto::SHA256HashString(JSONValue(),
&hash, crypto::kSHA256Length);
the 3rd argument should be sizeof(hash). (It's the same thing now, but it's more
robust to changes.)

[Takashi Toyoshima, 2015-03-19 13:00:21]

lgtm for media/midi.

[Adam Goode, 2015-03-19 16:48:32]

https://codereview.chromium.org/1020783002/diff/40001/media/midi/midi_manager...
File media/midi/midi_manager_alsa.cc (right):

https://codereview.chromium.org/1020783002/diff/40001/media/midi/midi_manager...
media/midi/midi_manager_alsa.cc:433: crypto::SHA256HashString(JSONValue(),
&hash, crypto::kSHA256Length);
On 2015/03/19 12:05:18, agl wrote:
> the 3rd argument should be sizeof(hash). (It's the same thing now, but it's
more
> robust to changes.)

Done.

[wolenetz, 2015-03-19 19:43:37]

media/DEPS lgtm

[Adam Goode, 2015-03-19 19:49:27]

The CQ bit was checked by agoode@chromium.org

[Adam Goode, 2015-03-19 19:49:28]

The patchset sent to the CQ was uploaded after l-g-t-m from
toyoshim@chromium.org, agl@chromium.org
Link to the patchset: https://codereview.chromium.org/1020783002/#ps60001
(title: "Use sizeof(hash) instead of repeating size constant")

[commit-bot: I haz the power, 2015-03-19 19:49:48]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1020783002/60001

[commit-bot: I haz the power, 2015-03-19 19:53:32]

Committed patchset #4 (id:60001)

[commit-bot: I haz the power, 2015-03-19 19:54:05]

Patchset 4 (id:??) landed as
https://crrev.com/eaea4405a27a01da0de837b09b542f54a31d5d00
Cr-Commit-Position: refs/heads/master@{#321412}