Split toolchain update and install lookup to make generation faster

Split toolchain update and install lookup to make generation faster

runhooks does toolchain update, saving relevant information to
build/win_toolchain.json, and during generation this is loaded
and used. This worked almost the same previously, however update
was called at generation time and the .json was deleted after
it was used. This speeds up generation time by a few seconds.

(In preference to https://codereview.chromium.org/228093002/)

R=dpranke@chromium.org
BUG=360878
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=262590

[Dirk Pranke, 2014-04-08 20:50:57]

lgtm w/ a nit ...

https://codereview.chromium.org/226643011/diff/20001/build/vs_toolchain.py
File build/vs_toolchain.py (right):

https://codereview.chromium.org/226643011/diff/20001/build/vs_toolchain.py#ne...
build/vs_toolchain.py:119: def UpdateOnly():
Nit: It's not clear to me what "UpdateOnly" means; what is the "only" an
alternative to?

Perhaps 'Update()' or 'UpdateToolchain()' ?

[scottmg, 2014-04-08 20:53:02]

https://codereview.chromium.org/226643011/diff/20001/build/vs_toolchain.py
File build/vs_toolchain.py (right):

https://codereview.chromium.org/226643011/diff/20001/build/vs_toolchain.py#ne...
build/vs_toolchain.py:119: def UpdateOnly():
On 2014/04/08 20:50:57, Dirk Pranke wrote:
> Nit: It's not clear to me what "UpdateOnly" means; what is the "only" an
> alternative to?
> 
> Perhaps 'Update()' or 'UpdateToolchain()' ? 

Done.

[scottmg, 2014-04-08 20:53:07]

The CQ bit was checked by scottmg@chromium.org

[commit-bot: I haz the power, 2014-04-08 20:55:54]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/scottmg@chromium.org/226643011/40001

[commit-bot: I haz the power, 2014-04-09 00:29:11]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/scottmg@chromium.org/226643011/40001

[commit-bot: I haz the power, 2014-04-09 00:53:32]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/scottmg@chromium.org/226643011/40001

[commit-bot: I haz the power, 2014-04-09 01:03:59]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/scottmg@chromium.org/226643011/40001

[commit-bot: I haz the power, 2014-04-09 01:24:56]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/scottmg@chromium.org/226643011/40001

[commit-bot: I haz the power, 2014-04-09 01:36:21]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/scottmg@chromium.org/226643011/40001

[commit-bot: I haz the power, 2014-04-09 01:47:29]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/scottmg@chromium.org/226643011/40001

[commit-bot: I haz the power, 2014-04-09 01:56:21]

Change committed as 262590