[Closure Externs] Generate closure compiler externs as part of compile

[Closure Externs] Generate closure compiler externs as part of compile

BUG=
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation

[Devlin, 2016-12-15 18:52:20]

Description was changed from

==========
[Closure Externs] Generate closure compiler externs as part of compile

BUG=
==========

to

==========
[Closure Externs] Generate closure compiler externs as part of compile

BUG=
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation
==========

[Devlin, 2016-12-15 18:56:40]

rdevlin.cronin@chromium.org changed reviewers:
+ dbeam@chromium.org

[Devlin, 2016-12-15 18:56:40]

Dan, mind taking a look?  This is still early on, so please ignore things like
debugging printfs - I'll clean it up and flesh out the CL description soon.  But
I'd like your help with where to put the compilation steps for closure compiler
and how to add a new file location.

That said, this patch actually *does* compile with closure, and updated
developer_private.idl results in an update to developer_private.js - woohoo!

https://codereview.chromium.org/2583573002/diff/20001/chrome/browser/extensio...
File chrome/browser/extensions/BUILD.gn (right):

https://codereview.chromium.org/2583573002/diff/20001/chrome/browser/extensio...
chrome/browser/extensions/BUILD.gn:829:
"//chrome/common/extensions/api:api_externs",
This causes the externs to be built as part of chrome.  Really, we just need to
do it as part of running closure compiler.  Is there a good place to put them
there?

https://codereview.chromium.org/2583573002/diff/20001/third_party/closure_com...
File third_party/closure_compiler/externs/compiled_resources2.gyp (right):

https://codereview.chromium.org/2583573002/diff/20001/third_party/closure_com...
third_party/closure_compiler/externs/compiled_resources2.gyp:48: 'target_name':
'../../../out/gnd/gen/third_party/closure_compiler/externs/developer_private',
This is obviously wrong. :)  How should this be?

[Dan Beam, 2016-12-16 05:39:53]

https://codereview.chromium.org/2583573002/diff/20001/third_party/closure_com...
File third_party/closure_compiler/externs/compiled_resources2.gyp (right):

https://codereview.chromium.org/2583573002/diff/20001/third_party/closure_com...
third_party/closure_compiler/externs/compiled_resources2.gyp:48: 'target_name':
'../../../out/gnd/gen/third_party/closure_compiler/externs/developer_private',
On 2016/12/15 18:56:40, Devlin wrote:
> This is obviously wrong. :)  How should this be?

it's hard to say exactly how GYP and GN should share this info (or if they
should).

if closure was GN, it would be easier.

it's possible that something like SHARED_INTERMEDIATE_DIR might work, but I'm
worried
https://gyp.gsrc.io/docs/InputFormatReference.md#Predefined-Variables

we could also just generate to somewhere in src/ and add the generated files to
.gitignore... but all of these are less nice than sharing GN between both
systems

[Devlin, 2016-12-16 23:50:15]

Description was changed from

==========
[Closure Externs] Generate closure compiler externs as part of compile

BUG=
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation
==========

to

==========
[Closure Externs] Generate closure compiler externs as part of compile

BUG=
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation
==========

[Devlin, 2016-12-16 23:50:15]

rdevlin.cronin@chromium.org changed reviewers:
+ dpranke@chromium.org

[Devlin, 2016-12-16 23:51:03]

On 2016/12/16 05:39:53, Dan Beam wrote:
>
https://codereview.chromium.org/2583573002/diff/20001/third_party/closure_com...
> File third_party/closure_compiler/externs/compiled_resources2.gyp (right):
> 
>
https://codereview.chromium.org/2583573002/diff/20001/third_party/closure_com...
> third_party/closure_compiler/externs/compiled_resources2.gyp:48:
'target_name':
> '../../../out/gnd/gen/third_party/closure_compiler/externs/developer_private',
> On 2016/12/15 18:56:40, Devlin wrote:
> > This is obviously wrong. :)  How should this be?
> 
> it's hard to say exactly how GYP and GN should share this info (or if they
> should).
> 
> if closure was GN, it would be easier.
> 
> it's possible that something like SHARED_INTERMEDIATE_DIR might work, but I'm
> worried
> https://gyp.gsrc.io/docs/InputFormatReference.md#Predefined-Variables
> 
> we could also just generate to somewhere in src/ and add the generated files
to
> .gitignore... but all of these are less nice than sharing GN between both
> systems

+gyp/gn master dpranke@ for his opinions.  I'm not super keen on adding files to
src/ directly; I'd much rather have generated files go in the gen/ directory.

I thought we also had a project to move closure to gn - is that still happening?
 Is there a timeline?

[Dirk Pranke, 2017-01-09 05:20:02]

The move to GN was supposed to happen months ago, but someone (*cough* *cough*)
has failed to actually do that work :(.

It's unclear to me if I'm going to have the time to it any time soon given my
new role and work schedule. Maybe later this week we can meet to discuss what we
should try to do?

https://codereview.chromium.org/2583573002/diff/20001/third_party/closure_com...
File third_party/closure_compiler/externs/compiled_resources2.gyp (right):

https://codereview.chromium.org/2583573002/diff/20001/third_party/closure_com...
third_party/closure_compiler/externs/compiled_resources2.gyp:48: 'target_name':
'../../../out/gnd/gen/third_party/closure_compiler/externs/developer_private',
On 2016/12/16 05:39:52, Dan Beam wrote:
> On 2016/12/15 18:56:40, Devlin wrote:
> > This is obviously wrong. :)  How should this be?
> 
> it's hard to say exactly how GYP and GN should share this info (or if they
> should).
> 
> if closure was GN, it would be easier.
> 
> it's possible that something like SHARED_INTERMEDIATE_DIR might work, but I'm
> worried
> https://gyp.gsrc.io/docs/InputFormatReference.md#Predefined-Variables
> 
> we could also just generate to somewhere in src/ and add the generated files
to
> .gitignore... but all of these are less nice than sharing GN between both
> systems

We shouldn't generate things into src/. I'm not sure if SHARED_INTERMEDIATE_DIR
will work, but it's worth trying. Otherwise I'd be fine w/ just getting some
hack working until we can move to GN.