Support references to args files in MB.

Support references to args files in MB.

Eventually we want most of the MB implementation to go away;
in particular, we probably want the bots to pick up their
GN configurations from args files, rather than from configs
in the mb_config.pyl file.

This CL adds support for specifying a given args file for a bot
in the master/builder configs directly, so you can specify
"masters": {"master": {"builder": "//foo/bar/baz.gn"}}. When
MB runs, it'll create an args.gn in the build directory that
contains the line 'import("//foo/bar/baz.gn")', which will
ensure the args are kept in sync.

R=brettw@chromium.org, jessicag@chromium.org, perezju@chromium.org
BUG=602528
Committed: https://crrev.com/9dd5e25ac7e13a059c68e71b8a22955d952c23a3
Cr-Commit-Position: refs/heads/master@{#387234}

[Dirk Pranke, 2016-04-12 03:11:01]

Please take a look; I think this is roughly how I want things to work.

I'm a little bit uncertain as to whether we really want the per-bot configs to
live in //build (putting them in //infra might be better), but nothing
is hard-coded so we can move this whenever.

[perezju, 2016-04-12 10:40:53]

non-owner, nor really experienced with the inner workings of mb; but from a user
point of view this lgtm.

https://codereview.chromium.org/1881823002/diff/1/tools/mb/mb.py
File tools/mb/mb.py (right):

https://codereview.chromium.org/1881823002/diff/1/tools/mb/mb.py#newcode318
tools/mb/mb.py:318: all_configs[config] = master
nit: I think this line shouldn't change

[Dirk Pranke, 2016-04-12 15:15:45]

https://codereview.chromium.org/1881823002/diff/1/tools/mb/mb.py
File tools/mb/mb.py (right):

https://codereview.chromium.org/1881823002/diff/1/tools/mb/mb.py#newcode318
tools/mb/mb.py:318: all_configs[config] = master
On 2016/04/12 10:40:53, perezju wrote:
> nit: I think this line shouldn't change

You're right.

[brettw, 2016-04-12 21:52:13]

https://codereview.chromium.org/1881823002/diff/1/build/args/bots/official.de...
File build/args/bots/official.desktop/blimp-engine.gn (right):

https://codereview.chromium.org/1881823002/diff/1/build/args/bots/official.de...
build/args/bots/official.desktop/blimp-engine.gn:2: is_debug = true
I'd expect a bot generically named and especially in the "official" category
wouldn't be debug. I think either the name of this config or the config itself
should change.

[Dirk Pranke, 2016-04-12 21:58:33]

https://codereview.chromium.org/1881823002/diff/1/build/args/bots/official.de...
File build/args/bots/official.desktop/blimp-engine.gn (right):

https://codereview.chromium.org/1881823002/diff/1/build/args/bots/official.de...
build/args/bots/official.desktop/blimp-engine.gn:2: is_debug = true
On 2016/04/12 21:52:13, brettw wrote:
> I'd expect a bot generically named and especially in the "official" category
> wouldn't be debug. I think either the name of this config or the config itself
> should change.

I'm not trying to match the name of the config, I'm matching the name of the bot
("blimp-engine").

It is admittedly confusing that the builder on the official waterfall is doing
debug builds but that is in fact the case. I expect they'll fix this when blimp
is closer to actually shipping.

[brettw, 2016-04-12 21:59:12]

Hmm, weird. LGTM

[Jess, 2016-04-13 17:48:12]

lgtm

[Dirk Pranke, 2016-04-14 02:06:48]

The CQ bit was checked by dpranke@chromium.org

[Dirk Pranke, 2016-04-14 02:06:48]

The patchset sent to the CQ was uploaded after l-g-t-m from
perezju@chromium.org, jessicag@chromium.org, brettw@chromium.org
Link to the patchset: https://codereview.chromium.org/1881823002/#ps40001
(title: "fix indent")

[commit-bot: I haz the power, 2016-04-14 02:07:12]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1881823002/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1881823002/40001

[commit-bot: I haz the power, 2016-04-14 04:23:19]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2016-04-14 04:25:05]

Description was changed from

==========
Support references to args files in MB.

Eventually we want most of the MB implementation to go away;
in particular, we probably want the bots to pick up their
GN configurations from args files, rather than from configs
in the mb_config.pyl file.

This CL adds support for specifying a given args file for a bot
in the master/builder configs directly, so you can specify
"masters": {"master": {"builder": "//foo/bar/baz.gn"}}. When
MB runs, it'll create an args.gn in the build directory that
contains the line 'import("//foo/bar/baz.gn")', which will
ensure the args are kept in sync.

R=brettw@chromium.org, jessicag@chromium.org, perezju@chromium.org
BUG=602528
==========

to

==========
Support references to args files in MB.

Eventually we want most of the MB implementation to go away;
in particular, we probably want the bots to pick up their
GN configurations from args files, rather than from configs
in the mb_config.pyl file.

This CL adds support for specifying a given args file for a bot
in the master/builder configs directly, so you can specify
"masters": {"master": {"builder": "//foo/bar/baz.gn"}}. When
MB runs, it'll create an args.gn in the build directory that
contains the line 'import("//foo/bar/baz.gn")', which will
ensure the args are kept in sync.

R=brettw@chromium.org, jessicag@chromium.org, perezju@chromium.org
BUG=602528

Committed: https://crrev.com/9dd5e25ac7e13a059c68e71b8a22955d952c23a3
Cr-Commit-Position: refs/heads/master@{#387234}
==========

[commit-bot: I haz the power, 2016-04-14 04:25:06]

Patchset 3 (id:??) landed as
https://crrev.com/9dd5e25ac7e13a059c68e71b8a22955d952c23a3
Cr-Commit-Position: refs/heads/master@{#387234}