GN: refactor third_party/gni

GN: refactor third_party/gni

  This fixes the build on Linux (dep on third_party:zlib -> third_party/zlib).

  I've moved declare_args() {} back to each .gn file... seems like args want
  to be as local as possible in GN land.

  Additionally, refactor all the common third_party config and warning flag
  changes into a template, third_party.  This lets it all live together in a
  .gni: at head unwanted_configs can be in a .gni (it's just a variable) but
  config("no_warnings") (and thus third_party_configs) cannot, as configs
  cannot be part of .gni files.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2163653002

Committed: https://skia.googlesource.com/skia/+/f037d48e29000554abcd117445c4249071bb9fb3

[mtklein_C, 2016-07-19 14:28:54]

Description was changed from

==========
GN: refactor third_party/gni

  This fixes the build on Linux (dep on third_party:zlib -> third_party/zlib).

  Additionally, refactor all the common third_party config and warning flag
  changes into a template, third_party.  This lets it all live together in a
  .gni: at head unwanted_configs can be in a .gni (it's just a variable) but
  config("no_warnings") (and thus third_party_configs) cannot, as configs
  cannot be part of .gni files.

BUG=skia:
==========

to

==========
GN: refactor third_party/gni

  This fixes the build on Linux (dep on third_party:zlib -> third_party/zlib).

  Additionally, refactor all the common third_party config and warning flag
  changes into a template, third_party.  This lets it all live together in a
  .gni: at head unwanted_configs can be in a .gni (it's just a variable) but
  config("no_warnings") (and thus third_party_configs) cannot, as configs
  cannot be part of .gni files.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2163653002
==========

[mtklein_C, 2016-07-19 14:31:02]

Description was changed from

==========
GN: refactor third_party/gni

  This fixes the build on Linux (dep on third_party:zlib -> third_party/zlib).

  Additionally, refactor all the common third_party config and warning flag
  changes into a template, third_party.  This lets it all live together in a
  .gni: at head unwanted_configs can be in a .gni (it's just a variable) but
  config("no_warnings") (and thus third_party_configs) cannot, as configs
  cannot be part of .gni files.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2163653002
==========

to

==========
GN: refactor third_party/gni

  This fixes the build on Linux (dep on third_party:zlib -> third_party/zlib).

  I've moved declare_args() {} back to each .gn file... seems like args want
  to be as local as possible in GN land.

  Additionally, refactor all the common third_party config and warning flag
  changes into a template, third_party.  This lets it all live together in a
  .gni: at head unwanted_configs can be in a .gni (it's just a variable) but
  config("no_warnings") (and thus third_party_configs) cannot, as configs
  cannot be part of .gni files.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2163653002
==========

[mtklein_C, 2016-07-19 14:32:20]

mtklein@chromium.org changed reviewers:
+ jcgregorio@google.com

[mtklein_C, 2016-07-19 14:32:20]

The CQ bit was checked by mtklein@chromium.org

[commit-bot: I haz the power, 2016-07-19 14:32:26]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[abarth, 2016-07-19 14:33:55]

abarth@google.com changed reviewers:
+ abarth@google.com

[abarth, 2016-07-19 14:33:56]

Oh, good idea to use a template.

[mtklein_C, 2016-07-19 14:54:52]

On 2016/07/19 at 14:33:56, abarth wrote:
> Oh, good idea to use a template.

I've found templates somewhat fussy before---I can never seem to get the
ordering right for a situation where a template wants to set some defaults and
an instance of it wants to tweak them---but in this case, it should be rare that
our third_party packages need to fiddle with custom warning flags.

[jcgregorio, 2016-07-19 15:23:11]

lgtm

[commit-bot: I haz the power, 2016-07-19 15:25:02]

Description was changed from

==========
GN: refactor third_party/gni

  This fixes the build on Linux (dep on third_party:zlib -> third_party/zlib).

  I've moved declare_args() {} back to each .gn file... seems like args want
  to be as local as possible in GN land.

  Additionally, refactor all the common third_party config and warning flag
  changes into a template, third_party.  This lets it all live together in a
  .gni: at head unwanted_configs can be in a .gni (it's just a variable) but
  config("no_warnings") (and thus third_party_configs) cannot, as configs
  cannot be part of .gni files.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2163653002
==========

to

==========
GN: refactor third_party/gni

  This fixes the build on Linux (dep on third_party:zlib -> third_party/zlib).

  I've moved declare_args() {} back to each .gn file... seems like args want
  to be as local as possible in GN land.

  Additionally, refactor all the common third_party config and warning flag
  changes into a template, third_party.  This lets it all live together in a
  .gni: at head unwanted_configs can be in a .gni (it's just a variable) but
  config("no_warnings") (and thus third_party_configs) cannot, as configs
  cannot be part of .gni files.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2163653002

Committed:
https://skia.googlesource.com/skia/+/f037d48e29000554abcd117445c4249071bb9fb3
==========

[commit-bot: I haz the power, 2016-07-19 15:25:03]

Committed patchset #2 (id:20001) as
https://skia.googlesource.com/skia/+/f037d48e29000554abcd117445c4249071bb9fb3