add a use_alsa gyp setting

add a use_alsa gyp setting

By adding a gyp setting, we can explicitly disable alsa on various
unix targets that don't include alsa.

BUG=

TEST=Build with use_alsa=0 then run ldd on output binaries to verify libasound is not listed (and is listed if built with use_alsa=1 or unspecified).


Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=185011

[DaleCurtis, 2013-02-21 20:57:29]

lgtm

https://codereview.chromium.org/12316049/diff/1/media/media.gyp
File media/media.gyp (right):

https://codereview.chromium.org/12316049/diff/1/media/media.gyp#newcode559
media/media.gyp:559: ['use_alsa==1', {
Long term, ideally, I'd like to get rid of all the use_alsa, use_cras, use_pulse
flags and just dlsym the libraries at runtime instead.

OOC what output driver are you using if not Alsa? Pulse, CrAS, something else?

[Mostyn Bramley-Moore, 2013-02-21 21:34:43]

We are integrating with a number of different embedded linux platforms that
provide their own custom interfaces.  A dlopen/dlsym based setup would probably
work really well for our use case.

I'm still learning the dev process here- are you able to start a test run on the
try server for me?

[no longer working on chromium, 2013-02-22 13:20:54]

On 2013/02/21 21:34:43, Mostyn Bramley-Moore wrote:
> We are integrating with a number of different embedded linux platforms that
> provide their own custom interfaces.  A dlopen/dlsym based setup would
probably
> work really well for our use case.
> 
> I'm still learning the dev process here- are you able to start a test run on
the
> try server for me?

Definitely we should use dynamic linking for the ALSA too.
We are doing this for Pulse in https://codereview.chromium.org/10952024/. I am
going to check if it affect the startup time for Chrome, if things look good, I
will add dynamic linking to alsa as well.

[DaleCurtis, 2013-02-22 21:15:02]

Once you have approval you can just click the 'CQ' button and the patch will
automatically be tested and committed if it passes tests.

[commit-bot: I haz the power, 2013-02-27 16:44:23]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/mostynb@opera.com/12316049/1

[commit-bot: I haz the power, 2013-02-27 19:58:15]

Change committed as 185011