[NaCl SDK] Change KernelProxy::GetCWD() to allocate path.

[NaCl SDK] Change KernelProxy::GetCWD() to allocate path.

When supplying a zero size to getcwd() typical behavior is to allocate
internally and return a pointer.  This behavior was already implemented, but
disabled by checking if size <= 0 and erroring with EINVAL.  As size_t is
positive definite, this entire check can be removed.

R=noelallen@chromium.org, sbc@chromium.org, binji@chromium.org
BUG=

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=244213

[binji, 2014-01-03 18:30:21]

lgtm, thanks!

Please add your name to the native_client_sdk/src/AUTHORS file, and make sure
you've signed the CLA (or CCLA):
http://code.google.com/legal/individual-cla-v1.0.html
http://code.google.com/legal/corporate-cla-v1.0.html

[Matthew Turk, 2014-01-03 18:50:34]

On 2014/01/03 18:30:21, binji wrote:
> lgtm, thanks!
> 
> Please add your name to the native_client_sdk/src/AUTHORS file, and make sure
> you've signed the CLA (or CCLA):
> http://code.google.com/legal/individual-cla-v1.0.html
> http://code.google.com/legal/corporate-cla-v1.0.html

Thanks!  I've signed the CLA in support of naclports so unless I need to sign a
separate one for Chromium I should be set.  I've updated with my name in the
AUTHORS file.

[commit-bot: I haz the power, 2014-01-08 18:34:37]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/matthewturk@gmail.com/122943005/60001

[commit-bot: I haz the power, 2014-01-08 18:57:08]

Retried try job too often on chromium_presubmit for step(s) presubmit
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=chromium_p...

[Matthew Turk, 2014-01-08 19:12:43]

On 2014/01/08 18:57:08, I haz the power (commit-bot) wrote:
> Retried try job too often on chromium_presubmit for step(s) presubmit
>
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=chromium_p...

Looking over the logs from the trybot, looks like it's failing on presubmit for
my name not being in AUTHORS, unless there's something else I'm missing.  Does
it need to be duplicated in both native_client_sdk/src/AUTHORS and in the
top-level AUTHORS?

[Sam Clegg, 2014-01-10 17:13:11]

lgtm

[commit-bot: I haz the power, 2014-01-10 17:18:28]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/matthewturk@gmail.com/122943005/210001

[commit-bot: I haz the power, 2014-01-10 19:14:55]

Change committed as 244213