Flip ClangToTLinux builder to GN

Flip ClangToTLinux builder to GN.

In the GYP build, this builder was using linux_dump_symbols
to make sure that we were getting debug symbols in a release (optimized) build, but in GN we can accomplish that by
simply passing the symbol_level=2 build arg instead.

R=brettw@chromium.org, thakis@chromium.org
BUG=605819
Committed: https://crrev.com/1ae814d2d836ea64a076b0a6d193d83098e812d4
Cr-Commit-Position: refs/heads/master@{#395786}

[brettw, 2016-05-24 18:11:25]

Changing the bot sounds good to me. Why does the bot even need this?

[Dirk Pranke, 2016-05-24 18:30:05]

On 2016/05/24 18:11:25, brettw wrote:
> Changing the bot sounds good to me. Why does the bot even need this?

From line 1733 in mb_config.pyl:
# Enable debug info, as on official builders, to catch issues with
# optimized debug info.

It's a different code path for the clang bots to test.

But you could accomplish this w/ an official build as well, I think.

[Nico, 2016-05-24 20:32:36]

official builds now use LTO builds, so I think they wouldn't check that
optimized debug info works (at least not at compile time).

[Dirk Pranke, 2016-05-24 21:18:36]

On 2016/05/24 20:32:36, Nico wrote:
> official builds now use LTO builds, so I think they wouldn't check that
> optimized debug info works (at least not at compile time).

Ok, per offline conversation w/ thakis it looks like all we really care about is
that we build w/ optimize + debug.

I had failed to realize that linux_dump_symbols actually was setting -g in
addition to doing the dump_syms 
action; thakis@ cares about the -g, but not the dump_syms action, so we can more
easily accommodate this
via symbol_level=2.

[Dirk Pranke, 2016-05-24 22:31:13]

Description was changed from

==========
Implement linux_dump_symbols for GN.

This isn't really needed as a flag, except that we have one Clang ToT
bot that builds with this but doesn't do an official build.

Arguably we should just have that bot do an official build and get rid
of the arg instead.

R=brettw@chromium.org, thakis@chromium.org
BUG=605819
==========

to

==========
Flip ClangToTLinux builder to GN.

In the GYP build, this builder was using linux_dump_symbols
to make sure that we were getting debug symbols in a release (optimized) build,
but in GN we can accomplish that by
simply passing the symbol_level=2 build arg instead.

R=brettw@chromium.org, thakis@chromium.org
BUG=605819
==========

[Dirk Pranke, 2016-05-24 22:33:03]

Patchset #3 (id:40001) has been deleted

[Dirk Pranke, 2016-05-24 22:33:45]

Okay, updated. PTAL?

[Nico, 2016-05-24 22:49:58]

lgtm

https://codereview.chromium.org/2008713003/diff/60001/chrome/BUILD.gn
File chrome/BUILD.gn (right):

https://codereview.chromium.org/2008713003/diff/60001/chrome/BUILD.gn#newcode...
chrome/BUILD.gn:1498: if (linux_dump_symbols) {
are you sure you want to change this file still?

[Dirk Pranke, 2016-05-24 23:32:51]

https://codereview.chromium.org/2008713003/diff/60001/chrome/BUILD.gn
File chrome/BUILD.gn (right):

https://codereview.chromium.org/2008713003/diff/60001/chrome/BUILD.gn#newcode...
chrome/BUILD.gn:1498: if (linux_dump_symbols) {
On 2016/05/24 22:49:58, Nico wrote:
> are you sure you want to change this file still?

oh, bah. I thought I reverted those changes. Good catch.

[Dirk Pranke, 2016-05-24 23:32:56]

The CQ bit was checked by dpranke@chromium.org

[Dirk Pranke, 2016-05-24 23:32:57]

The patchset sent to the CQ was uploaded after l-g-t-m from thakis@chromium.org
Link to the patchset: https://codereview.chromium.org/2008713003/#ps80001
(title: "revert BUILD.gn changes")

[commit-bot: I haz the power, 2016-05-24 23:33:52]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/2008713003/80001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/2008713003/80001

[commit-bot: I haz the power, 2016-05-25 03:00:07]

Description was changed from

==========
Flip ClangToTLinux builder to GN.

In the GYP build, this builder was using linux_dump_symbols
to make sure that we were getting debug symbols in a release (optimized) build,
but in GN we can accomplish that by
simply passing the symbol_level=2 build arg instead.

R=brettw@chromium.org, thakis@chromium.org
BUG=605819
==========

to

==========
Flip ClangToTLinux builder to GN.

In the GYP build, this builder was using linux_dump_symbols
to make sure that we were getting debug symbols in a release (optimized) build,
but in GN we can accomplish that by
simply passing the symbol_level=2 build arg instead.

R=brettw@chromium.org, thakis@chromium.org
BUG=605819
==========

[commit-bot: I haz the power, 2016-05-25 03:00:08]

Committed patchset #4 (id:80001)

[commit-bot: I haz the power, 2016-05-25 03:01:48]

Description was changed from

==========
Flip ClangToTLinux builder to GN.

In the GYP build, this builder was using linux_dump_symbols
to make sure that we were getting debug symbols in a release (optimized) build,
but in GN we can accomplish that by
simply passing the symbol_level=2 build arg instead.

R=brettw@chromium.org, thakis@chromium.org
BUG=605819
==========

to

==========
Flip ClangToTLinux builder to GN.

In the GYP build, this builder was using linux_dump_symbols
to make sure that we were getting debug symbols in a release (optimized) build,
but in GN we can accomplish that by
simply passing the symbol_level=2 build arg instead.

R=brettw@chromium.org, thakis@chromium.org
BUG=605819

Committed: https://crrev.com/1ae814d2d836ea64a076b0a6d193d83098e812d4
Cr-Commit-Position: refs/heads/master@{#395786}
==========

[commit-bot: I haz the power, 2016-05-25 03:01:50]

Patchset 4 (id:??) landed as
https://crrev.com/1ae814d2d836ea64a076b0a6d193d83098e812d4
Cr-Commit-Position: refs/heads/master@{#395786}