Hook up link pools in GN.

Committed: https://crrev.com/d54674267a8569ea90c5f8512eff690bcb86b1d4
Cr-Commit-Position: refs/heads/master@{#292261}

[brettw, 2014-08-26 21:25:04]

brettw@chromium.org changed reviewers:
+ scottmg@chromium.org

[scottmg, 2014-08-26 22:41:49]

lgtm

https://codereview.chromium.org/508763002/diff/20001/tools/gn/function_toolch...
File tools/gn/function_toolchain.cc (right):

https://codereview.chromium.org/508763002/diff/20001/tools/gn/function_toolch...
tools/gn/function_toolchain.cc:237: "    there is no limit to \"alink\" steps.
Defaults to 4.\n"
It ends up being 16 for gyp on a z620 fwiw. I don't know how much it matters.

https://codereview.chromium.org/508763002/diff/20001/tools/gn/toolchain.cc
File tools/gn/toolchain.cc (right):

https://codereview.chromium.org/508763002/diff/20001/tools/gn/toolchain.cc#ne...
tools/gn/toolchain.cc:27: concurrent_links_(4),
I think 0 might be a better hardcoded default (I think that un-limits)

[brettw, 2014-08-26 23:01:49]

I made the default 0 and documented this.

After I push the new binary I will check in a script that contains the logic
from GYP to compute the concurrent build number, and then run this script to
populate the value for the toolchain.

[brettw, 2014-08-27 23:05:12]

Committed patchset #3 (id:40001) to pending queue manually as 2f6d6c1 (presubmit
successful).

[commit-bot: I haz the power, 2014-09-10 02:55:24]

Patchset 3 (id:??) landed as
https://crrev.com/d54674267a8569ea90c5f8512eff690bcb86b1d4
Cr-Commit-Position: refs/heads/master@{#292261}