Add GN template for generated extensions API targets.

Add GN template for generated extensions API targets.

This adds a new GN template for generating static extensions API
library bundles from sets of schemas. It also adds invocations of
the template for core extensions and apps API targets.

BUG=None
TBR=kalman

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=266341

[Ken Rockot(use gerrit already), 2014-04-24 02:01:16]

Brett, could you please review GN content and let me know if I'm doing anything
stupid?

Ben, more of an FYI in case GN isn't yet on your radar. This provides a
replacement for corresponding api.gyp files and their json_schema_*compiler.gypi
friends.

The chrome_api target can't yet be ported due to some dependencies which still
lack GN support.

[not at google - send to devlin, 2014-04-24 15:00:17]

Converting to GN sounds awesome! Though I'd have expected there to be more gyp
code to delete (never seen a GN file)?

[not at google - send to devlin, 2014-04-24 15:00:42]

On 2014/04/24 15:00:17, kalman wrote:
> Converting to GN sounds awesome! Though I'd have expected there to be more gyp
> code to delete (never seen a GN file)?

I.e. I have never seen a GN file nor a CL for gyp --> gn.

[Ken Rockot(use gerrit already), 2014-04-24 15:07:16]

On 2014/04/24 15:00:42, kalman wrote:
> On 2014/04/24 15:00:17, kalman wrote:
> > Converting to GN sounds awesome! Though I'd have expected there to be more
gyp
> > code to delete (never seen a GN file)?
> 
> I.e. I have never seen a GN file nor a CL for gyp --> gn.

I think the two must coexist until the project is ready to switch entirely.

[brettw, 2014-04-24 18:29:44]

Impressive! Just some minor comments. LGTM with this addressed.

https://codereview.chromium.org/256453002/diff/1/extensions/generated_extensi...
File extensions/generated_extensions_api.gni (right):

https://codereview.chromium.org/256453002/diff/1/extensions/generated_extensi...
extensions/generated_extensions_api.gni:12: # schemas [required] A list of
schema files to be compiled.
I'm thinking we should generally name this kind of thing "sources" so you never
have to remember what it's called for different template types.

https://codereview.chromium.org/256453002/diff/1/extensions/generated_extensi...
extensions/generated_extensions_api.gni:61: "$compiler_root/cc_generator.py",
Be consistent with the indenting. I would use 2 spaces here like you do below.

https://codereview.chromium.org/256453002/diff/1/extensions/generated_extensi...
extensions/generated_extensions_api.gni:70: "$compiler_root/util_cc_helper.py" ]
For these multiline lists, I put the ] on the next line and add a comma after
the last element so its easier to add and remove items.

https://codereview.chromium.org/256453002/diff/1/extensions/generated_extensi...
extensions/generated_extensions_api.gni:90: "--root=" + rebase_path("//",
root_build_dir),
FWIW I have no way to tell if this is correct other than the output works, so I
didn't look at the details of the commands you're running. I'm assuming we can
fix them if they need tweaking later.

https://codereview.chromium.org/256453002/diff/1/extensions/generated_extensi...
extensions/generated_extensions_api.gni:99: "$target_gen_dir/generated_api.cc",
Ditto previous comments.

https://codereview.chromium.org/256453002/diff/1/extensions/generated_extensi...
extensions/generated_extensions_api.gni:118: static_library(target_name) {
CAn this be a source_set instead of a static_library?

[Ken Rockot(use gerrit already), 2014-04-24 19:39:54]

https://codereview.chromium.org/256453002/diff/1/extensions/generated_extensi...
File extensions/generated_extensions_api.gni (right):

https://codereview.chromium.org/256453002/diff/1/extensions/generated_extensi...
extensions/generated_extensions_api.gni:12: # schemas [required] A list of
schema files to be compiled.
On 2014/04/24 18:29:44, brettw wrote:
> I'm thinking we should generally name this kind of thing "sources" so you
never
> have to remember what it's called for different template types.

Debated this for a while myself. I agree with your reasoning. Done.

https://codereview.chromium.org/256453002/diff/1/extensions/generated_extensi...
extensions/generated_extensions_api.gni:61: "$compiler_root/cc_generator.py",
On 2014/04/24 18:29:44, brettw wrote:
> Be consistent with the indenting. I would use 2 spaces here like you do below.

Done. Force of habit from C++ style...

https://codereview.chromium.org/256453002/diff/1/extensions/generated_extensi...
extensions/generated_extensions_api.gni:70: "$compiler_root/util_cc_helper.py" ]
On 2014/04/24 18:29:44, brettw wrote:
> For these multiline lists, I put the ] on the next line and add a comma after
> the last element so its easier to add and remove items.

Done.

https://codereview.chromium.org/256453002/diff/1/extensions/generated_extensi...
extensions/generated_extensions_api.gni:90: "--root=" + rebase_path("//",
root_build_dir),
On 2014/04/24 18:29:44, brettw wrote:
> FWIW I have no way to tell if this is correct other than the output works, so
I
> didn't look at the details of the commands you're running. I'm assuming we can
> fix them if they need tweaking later.

Yep. I' pretty confident the arguments are conceptually correct. My main concern
is that I'm not sure if rebase_path("//", root_build_dir) is the best/idiomatic
way to generate a string which means "the chromium src root relative to cwd" to
an external script.

https://codereview.chromium.org/256453002/diff/1/extensions/generated_extensi...
extensions/generated_extensions_api.gni:118: static_library(target_name) {
On 2014/04/24 18:29:44, brettw wrote:
> CAn this be a source_set instead of a static_library?

I guess I don't see why it couldn't. Done.

Some day maybe we'd like APIs to be shared libraries, but that's neither here
nor there.

[Ken Rockot(use gerrit already), 2014-04-24 19:40:02]

The CQ bit was checked by rockot@chromium.org

[not at google - send to devlin, 2014-04-24 19:47:50]

lgtm

[commit-bot: I haz the power, 2014-04-24 21:47:54]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/rockot@chromium.org/256453002/20001

[commit-bot: I haz the power, 2014-04-24 23:37:16]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-04-24 23:37:17]

Try jobs failed on following builders:
  tryserver.chromium on win_chromium_x64_rel

[Ken Rockot(use gerrit already), 2014-04-25 04:14:27]

On 2014/04/24 23:37:17, I haz the power (commit-bot) wrote:
> Try jobs failed on following builders:
>   tryserver.chromium on win_chromium_x64_rel

Ah. Skia still isn't usable. Commented out extensions_api in the root group for
now.

[Ken Rockot(use gerrit already), 2014-04-25 04:14:35]

The CQ bit was checked by rockot@chromium.org

[commit-bot: I haz the power, 2014-04-25 08:13:29]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/rockot@chromium.org/256453002/60001

[commit-bot: I haz the power, 2014-04-25 22:38:06]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-04-25 22:38:07]

Try jobs failed on following builders:
  tryserver.chromium on linux_chromium_chromeos_rel

[Ken Rockot(use gerrit already), 2014-04-25 22:54:59]

The CQ bit was checked by rockot@chromium.org

[commit-bot: I haz the power, 2014-04-25 22:56:17]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/rockot@chromium.org/256453002/60001

[commit-bot: I haz the power, 2014-04-26 09:56:11]

Change committed as 266341