Web MIDI: Add a run-time flag

Web MIDI: Add a run-time flag

The flag is disabled by default for now.
--enable-web-midi command line flag enables a run-time flag for Web MIDI .
But it doesn't work for now.

BUG=163795
TEST=none

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=195766

[Takashi Toyoshima, 2013-04-19 05:06:23]

I Brett,

Can you take a look this change to add a runtime flag as a content/OWNERS?
This is the first change to implement Web MIDI since blink API review grant to
go ahead.

[Chris Rogers, 2013-04-20 01:02:06]

Thanks Takashi, I'm wondering if we need to put this behind a compile-time flag
or is run-time checking sufficient.

Also, I'd recommend waiting a little while before we have this appear in
"about:flags" until we have more of the implementation in place.  It seems
better to have something working so that people don't get frustrated trying to
turn it on there.  A command-line option to enable it seems ok until then - not
sure what others think.

[Takashi Toyoshima, 2013-04-20 02:06:20]

Thanks.

Using run-time flag make it easy to keep my implementation green. So, I prefer
run-time flag. At that time, I need to land runtime flag change in blink
firstly. I'll send it soon.

How about having about:flags behind a compile-time flag? Having it looks useful
to us, developers.

[Chris Rogers, 2013-04-20 02:33:41]

On 2013/04/20 02:06:20, Takashi Toyoshima (chromium) wrote:
> Thanks.
> 
> Using run-time flag make it easy to keep my implementation green. So, I prefer
> run-time flag. At that time, I need to land runtime flag change in blink
> firstly. I'll send it soon.
> 
> How about having about:flags behind a compile-time flag? Having it looks
useful
> to us, developers.

For testing and development, isn't it sufficient to just launch chrome with
--enable-webmidi command-line flag?

[brettw, 2013-04-22 05:41:09]

Is the GYP_DEFINE added only to support a two-sided landing in Blink?

LGTM if you're planning on removing the flag soon.

[Takashi Toyoshima, 2013-04-22 07:32:29]

I agreed with Chris's suggestion. So, I removed all compile-time flag. Blink
side change is now in CQ. So, I'll land this after the blink side change is
rolled.

[commit-bot: I haz the power, 2013-04-23 05:43:19]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/toyoshim@chromium.org/14241011/25001

[commit-bot: I haz the power, 2013-04-23 06:47:41]

Step "update" is always a major failure.
Look at the try server FAQ for more details.
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=linux_clan...

[commit-bot: I haz the power, 2013-04-23 07:01:13]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/toyoshim@chromium.org/14241011/25001

[commit-bot: I haz the power, 2013-04-23 08:08:15]

Step "update" is always a major failure.
Look at the try server FAQ for more details.
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win7_aura&...

[Takashi Toyoshima, 2013-04-23 08:40:45]

Committed patchset #5 manually as r195766 (presubmit successful).