Precompile mojom bindings generator jinja templates.

Precompile mojom bindings generator jinja templates.

Previously, the mojom bindings generator would use the jinja template
files directly, requiring relatively expensive conversion to Python
bytecode once for each mojom file. This adds template precompilation
and changes the generator to use the precompiled bytecode.

On a z620 running Linux, generating all mojo bindings using GN
Before:
real	0m11.729s
user	4m22.588s
sys	0m6.003s

After:
real	0m2.948s
user	0m33.126s
sys	0m4.564s

GYP (many mojom files are only used in GN builds)
Before:
real	0m9.822s
user	0m49.949s
sys	0m1.046s

After:
real	0m5.354s
user	0m4.776s
sys	0m0.998s

Committed: https://crrev.com/61d8b73f3d3891991f2afcd27fc40f5b09448e27
Cr-Commit-Position: refs/heads/master@{#369349}

[Sam McNally, 2016-01-11 07:01:35]

Description was changed from

==========
Precompile mojom bindings generator jinja templates.

This saves 3m50s of user CPU time (8s real time) on a z620 on Linux.
==========

to

==========
Precompile mojom bindings generator jinja templates.

Previously, the mojom bindings generator would use the jinja template
files directly, requiring relatively expensive conversion to Python
bytecode once for each mojom file. This adds template precompilation
and changes the generator to use the precompiled bytecode.

On a z620 running Linux, generating all mojo bindings using GN
Before:
real	0m11.729s
user	4m22.588s
sys	0m6.003s

After:
real	0m2.948s
user	0m33.126s
sys	0m4.564s

GYP (many mojom files are only used in GN builds)
Before:
real	0m9.822s
user	0m49.949s
sys	0m1.046s

After:
real	0m5.354s
user	0m4.776s
sys	0m0.998s
==========

[Sam McNally, 2016-01-11 07:19:58]

Patchset #1 (id:1) has been deleted

[Sam McNally, 2016-01-11 23:38:37]

Patchset #1 (id:20001) has been deleted

[Sam McNally, 2016-01-12 02:55:01]

sammc@chromium.org changed reviewers:
+ yzshen@chromium.org

[yzshen1, 2016-01-14 01:32:47]

Great to see such improvement!

LGTM with a few nits.

https://codereview.chromium.org/1572213002/diff/40001/mojo/public/tools/bindi...
File mojo/public/tools/bindings/BUILD.gn (right):

https://codereview.chromium.org/1572213002/diff/40001/mojo/public/tools/bindi...
mojo/public/tools/bindings/BUILD.gn:1: # Copyright 2015 The Chromium Authors.
All rights reserved.
2016, time flies! :) (here and other new files)

https://codereview.chromium.org/1572213002/diff/40001/mojo/public/tools/bindi...
mojo/public/tools/bindings/BUILD.gn:5: import("mojom.gni")
nit: please use absolute path.

https://chromium.googlesource.com/chromium/src/+/master/tools/gn/docs/style_g...

https://codereview.chromium.org/1572213002/diff/40001/mojo/public/tools/bindi...
File mojo/public/tools/bindings/mojom_bindings_generator.py (right):

https://codereview.chromium.org/1572213002/diff/40001/mojo/public/tools/bindi...
mojo/public/tools/bindings/mojom_bindings_generator.py:238:
metavar="GENERATORS",
nit: the indent is a little unusual.

https://codereview.chromium.org/1572213002/diff/40001/mojo/public/tools/bindi...
mojo/public/tools/bindings/mojom_bindings_generator.py:250: required=True)
please add "help".

[Sam McNally, 2016-01-14 02:55:58]

Patchset #2 (id:60001) has been deleted

[Sam McNally, 2016-01-14 02:58:19]

https://codereview.chromium.org/1572213002/diff/40001/mojo/public/tools/bindi...
File mojo/public/tools/bindings/BUILD.gn (right):

https://codereview.chromium.org/1572213002/diff/40001/mojo/public/tools/bindi...
mojo/public/tools/bindings/BUILD.gn:1: # Copyright 2015 The Chromium Authors.
All rights reserved.
On 2016/01/14 01:32:47, yzshen1 wrote:
> 2016, time flies! :) (here and other new files)

Done.

https://codereview.chromium.org/1572213002/diff/40001/mojo/public/tools/bindi...
mojo/public/tools/bindings/BUILD.gn:5: import("mojom.gni")
On 2016/01/14 01:32:47, yzshen1 wrote:
> nit: please use absolute path.
> 
>
https://chromium.googlesource.com/chromium/src/+/master/tools/gn/docs/style_g...

Done.

https://codereview.chromium.org/1572213002/diff/40001/mojo/public/tools/bindi...
File mojo/public/tools/bindings/mojom_bindings_generator.py (right):

https://codereview.chromium.org/1572213002/diff/40001/mojo/public/tools/bindi...
mojo/public/tools/bindings/mojom_bindings_generator.py:238:
metavar="GENERATORS",
On 2016/01/14 01:32:47, yzshen1 wrote:
> nit: the indent is a little unusual.

Done.

https://codereview.chromium.org/1572213002/diff/40001/mojo/public/tools/bindi...
mojo/public/tools/bindings/mojom_bindings_generator.py:250: required=True)
On 2016/01/14 01:32:47, yzshen1 wrote:
> please add "help".

Done.

[Sam McNally, 2016-01-14 02:58:26]

The CQ bit was checked by sammc@chromium.org

[Sam McNally, 2016-01-14 02:58:26]

The patchset sent to the CQ was uploaded after l-g-t-m from yzshen@chromium.org
Link to the patchset: https://codereview.chromium.org/1572213002/#ps80001
(title: " ")

[commit-bot: I haz the power, 2016-01-14 03:04:42]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1572213002/80001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1572213002/80001

[commit-bot: I haz the power, 2016-01-14 05:08:08]

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

[commit-bot: I haz the power, 2016-01-14 05:08:09]

Try jobs failed on following builders:
  android_arm64_dbg_recipe on tryserver.chromium.android (JOB_TIMED_OUT, no
build URL)
  android_chromium_gn_compile_dbg on tryserver.chromium.android (JOB_TIMED_OUT,
no build URL)
  android_chromium_gn_compile_rel on tryserver.chromium.android (JOB_TIMED_OUT,
no build URL)
  android_clang_dbg_recipe on tryserver.chromium.android (JOB_TIMED_OUT, no
build URL)
  android_compile_dbg on tryserver.chromium.android (JOB_TIMED_OUT, no build
URL)
  cast_shell_android on tryserver.chromium.android (JOB_TIMED_OUT, no build URL)

[Sam McNally, 2016-01-14 05:33:41]

The CQ bit was checked by sammc@chromium.org

[commit-bot: I haz the power, 2016-01-14 05:34:00]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1572213002/80001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1572213002/80001

[commit-bot: I haz the power, 2016-01-14 06:33:48]

Committed patchset #2 (id:80001)

[commit-bot: I haz the power, 2016-01-14 06:35:04]

Description was changed from

==========
Precompile mojom bindings generator jinja templates.

Previously, the mojom bindings generator would use the jinja template
files directly, requiring relatively expensive conversion to Python
bytecode once for each mojom file. This adds template precompilation
and changes the generator to use the precompiled bytecode.

On a z620 running Linux, generating all mojo bindings using GN
Before:
real	0m11.729s
user	4m22.588s
sys	0m6.003s

After:
real	0m2.948s
user	0m33.126s
sys	0m4.564s

GYP (many mojom files are only used in GN builds)
Before:
real	0m9.822s
user	0m49.949s
sys	0m1.046s

After:
real	0m5.354s
user	0m4.776s
sys	0m0.998s
==========

to

==========
Precompile mojom bindings generator jinja templates.

Previously, the mojom bindings generator would use the jinja template
files directly, requiring relatively expensive conversion to Python
bytecode once for each mojom file. This adds template precompilation
and changes the generator to use the precompiled bytecode.

On a z620 running Linux, generating all mojo bindings using GN
Before:
real	0m11.729s
user	4m22.588s
sys	0m6.003s

After:
real	0m2.948s
user	0m33.126s
sys	0m4.564s

GYP (many mojom files are only used in GN builds)
Before:
real	0m9.822s
user	0m49.949s
sys	0m1.046s

After:
real	0m5.354s
user	0m4.776s
sys	0m0.998s

Committed: https://crrev.com/61d8b73f3d3891991f2afcd27fc40f5b09448e27
Cr-Commit-Position: refs/heads/master@{#369349}
==========

[commit-bot: I haz the power, 2016-01-14 06:35:05]

Patchset 2 (id:??) landed as
https://crrev.com/61d8b73f3d3891991f2afcd27fc40f5b09448e27
Cr-Commit-Position: refs/heads/master@{#369349}