[infra] Prepare gn.py for update to GN binary

[infra] Prepare gn.py for update to GN binary

First part in attempt to reland https://codereview.chromium.org/2854583002/
in two parts. If the second part fails, this part does not need to be
reverted.

Committed: https://github.com/dart-lang/sdk/commit/c94667420a09020f0a810c069cdf899ce60ed2e7

[zra, 2017-05-03 22:23:29]

zra@google.com changed reviewers:
+ asiva@google.com

[zra, 2017-05-03 22:23:30]

TBR

[zra, 2017-05-03 22:23:45]

Description was changed from

==========
[infra] Prepare gn.py for update to GN binary

First part in attempt to reland https://codereview.chromium.org/2854583002/
in two parts. If the second part fails, this part does not need to be
reverted.
==========

to

==========
[infra] Prepare gn.py for update to GN binary

First part in attempt to reland https://codereview.chromium.org/2854583002/
in two parts. If the second part fails, this part does not need to be
reverted.

Committed:
https://github.com/dart-lang/sdk/commit/c94667420a09020f0a810c069cdf899ce60ed2e7
==========

[zra, 2017-05-03 22:23:46]

Committed patchset #1 (id:1) manually as
c94667420a09020f0a810c069cdf899ce60ed2e7 (presubmit successful).

[siva, 2017-05-04 05:14:32]

Not sure how this was running before with cpu count > 1

[zra, 2017-05-04 05:28:53]

On 2017/05/04 05:14:32, siva wrote:
> Not sure how this was running before with cpu count > 1

The newer version of GN being used by Fuchsia and Flutter was encountering
problems on the bots. I scaled this back to eliminate a possible source of the
problems, but it didn't help. This can probably be returned to the original
value, but I want to wait to do that until the update lands.

[siva, 2017-05-04 05:29:46]

On 2017/05/04 05:28:53, zra wrote:
> On 2017/05/04 05:14:32, siva wrote:
> > Not sure how this was running before with cpu count > 1
> 
> The newer version of GN being used by Fuchsia and Flutter was encountering
> problems on the bots. I scaled this back to eliminate a possible source of the
> problems, but it didn't help. This can probably be returned to the original
> value, but I want to wait to do that until the update lands.

Sounds good.