This won't make M-53, so I'm clearing the label.

I'm going to try tracking ship-blocking things via the label "Proj-GN-Migration-Ship" (instead of Proj-GN-Migration) as suggested w/ a conversation w/ laforge@ and the monorail folks a while ago.

Querying for "Proj=GN-Migration%" should still return bugs for both labels, and this will allow us to filter out rollup things more easily, so that we can use blocking just for things that are truly blocking other bugs.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/c724e93ce54205fa9dc57f0cd00429a40308c178

commit c724e93ce54205fa9dc57f0cd00429a40308c178
Author: dpranke <dpranke@chromium.org>
Date: Wed Jul 13 03:06:14 2016

Fix mac remoting GN build failures.

In the official GN builds on the mac, there were two issues w/ the GN
build. The first was that one of the targets was missing a dependency
and links could fail, and the second was that building the installer
would inadvertently delete a generated file, leading the build to always
be dirty.

R=rsesek@chromium.org, nicholss@chromium.org, brettw@chromium.org
BUG= 623685 

Review-Url: https://codereview.chromium.org/2142233002
Cr-Commit-Position: refs/heads/master@{#404941}

[modify] https://crrev.com/c724e93ce54205fa9dc57f0cd00429a40308c178/remoting/host/BUILD.gn

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/c724e93ce54205fa9dc57f0cd00429a40308c178

commit c724e93ce54205fa9dc57f0cd00429a40308c178
Author: dpranke <dpranke@chromium.org>
Date: Wed Jul 13 03:06:14 2016

Fix mac remoting GN build failures.

In the official GN builds on the mac, there were two issues w/ the GN
build. The first was that one of the targets was missing a dependency
and links could fail, and the second was that building the installer
would inadvertently delete a generated file, leading the build to always
be dirty.

R=rsesek@chromium.org, nicholss@chromium.org, brettw@chromium.org
BUG= 623685 

Review-Url: https://codereview.chromium.org/2142233002
Cr-Commit-Position: refs/heads/master@{#404941}

[modify] https://crrev.com/c724e93ce54205fa9dc57f0cd00429a40308c178/remoting/host/BUILD.gn

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/b231bcf64216a6d0d52f9e1017560c0d4720a5f3

commit b231bcf64216a6d0d52f9e1017560c0d4720a5f3
Author: dpranke <dpranke@chromium.org>
Date: Tue Jul 19 16:42:06 2016

Try again to flip the official mac builders to GN.

R=rsesek@chromium.org
BUG= 623685 

Review-Url: https://codereview.chromium.org/2155353002
Cr-Commit-Position: refs/heads/master@{#406294}

[modify] https://crrev.com/b231bcf64216a6d0d52f9e1017560c0d4720a5f3/tools/mb/mb_config.pyl

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/1b53b935fb9febdbc52456d8643b02a39c83b737

commit 1b53b935fb9febdbc52456d8643b02a39c83b737
Author: dpranke <dpranke@chromium.org>
Date: Tue Jul 19 19:16:40 2016

Downgrade Mac GN arg save_unstripped_output to just a variable.

It's not clear that we really need the GN arg `save_unstripped_output`
to be a user-configurable thing, so this change removes it from the
declare_arg() block in the build file and instead becomes a shorthand
for (enable_stripping && !enable_dsyms).

R=rsesek@chromium.org
BUG= 623685 ,  628052 

Review-Url: https://codereview.chromium.org/2163533002
Cr-Commit-Position: refs/heads/master@{#406338}

[modify] https://crrev.com/1b53b935fb9febdbc52456d8643b02a39c83b737/build/config/mac/symbols.gni

The builders have been flipped, just waiting for the official bots to cycle through ...

It looks like this might stick!

Mac official builders are still using GYP [m53]. Can we leave this bug open until we actually have the official builders using GN?

https://uberchromegw.corp.google.com/i/official.desktop/builders/mac64/builds/1133/steps/generate_build_files/logs/stdio

shows: 
"""
//out/Release/mb_type missing, clobbering to be safe
GYP_DEFINES='branding=Chrome buildtype=Official'
python build/gyp_chromium -G output_dir=out
Updating projects from gyp files...
Using overrides found in /Users/chrome-bot/.gyp/include.gypi
"""

"""
chrome-bot@osx-3-m0:(Mac 10.9.5):/b/build/slave/mac64/build/src$ cat /b/build/slave/mac64/build/src/tools/mb/mb_config.pyl | grep -C 3 official.desktop
      'blimp-engine': '//build/args/bots/official.android/blimp-engine.gn',
    },

    'official.desktop': {
      'mac64': 'gyp_official',
      'precise64': 'gn_official',

--
--
"""

that's weird...

git log:
"""
commit 809a28b2c812ad86e14268a6955b98bd43fc584a
Author: Alex Mineer <amineer@chromium.org>
Date:   Tue Aug 16 14:16:31 2016 -0700

    Fix Mac build config
    
    Cr-Commit-Position: refs/branch-heads/2785@{#632}
    Cr-Branched-From: 68623971be0cfc492a2cb0427d7f478e7b214c24-refs/heads/master@{#403382}

commit fe9020905f7661e93576f3424eeec0c04c41d66c
Author: Alex Mineer <amineer@chromium.org>
Date:   Thu Aug 11 16:07:56 2016 -0700

    Fix blimp-engine parent builder
    
    Cr-Commit-Position: refs/branch-heads/2785@{#568}
    Cr-Branched-From: 68623971be0cfc492a2cb0427d7f478e7b214c24-refs/heads/master@{#403382}

commit e362e8e8b5d68120868dc76bd3b9bb7da7d4f27f
Author: Dirk Pranke <dpranke@chromium.org>
Date:   Wed Jul 27 17:23:49 2016 -0700

    Implement multi-phase build support in MB (merge to M53)
"""

git log -p 809a28b2c812ad86e14268a6955b98bd43fc584a
--- a/tools/mb/mb_config.pyl
+++ b/tools/mb/mb_config.pyl
@@ -628,7 +628,7 @@
     },
 
     'official.desktop': {
-      'mac64': 'gn_official',
+      'mac64': 'gyp_official',
       'precise64': 'gn_official',
 
       # Currently the official bots set mini_installer_official_deps=1