commit 194fea620e1c1861193d53ff817b313f6a2b0a9a
author Tom Anderson <thomasanderson@chromium.org> Fri Feb 08 13:11:56 2019
committer Commit Bot <commit-bot@chromium.org> Fri Feb 08 13:11:56 2019
tree 47502687617710c149b4cff37c2c67c51f73d9b0
parent 3f30be234fbbc7907d376319b398bd98a9024788

Fix gn build on 'Build From Tarball' bot

This is necessary to green-up the 'Build From Tarball' bot.  The bot is running
Trusty, which has a system libstdc++ that's too old to support many of the
features in base that gn relies on.

Here's the story of why this is now necessary:

1. Chromium's gn was originally built with libc++ to get around this exact
   issue.
2. gn was moved into a standalone repo.
3. The libc++ sources weren't copied into standalone gn, so their solution to
   fix this issue was to pull Chromium's debian sysroot that has newer libstdc++
   headers.
4. For whatever reason, the option to build with the sysroot was removed from
   the public repository and now the bots have a step to pull the sysroot.

This can be removed once Ubuntu Trusty reaches EOL, or when Chromium's
infrastructure is upgraded from Trusty to Xenial, whichever comes second
ideally.

BUG=807400
R=thakis

Change-Id: I00901b3df4005f6ac098774822fffe12dd67e561
Reviewed-on: https://chromium-review.googlesource.com/c/1460187
Auto-Submit: Thomas Anderson <thomasanderson@chromium.org>
Commit-Queue: Nico Weber <thakis@chromium.org>
Reviewed-by: Nico Weber <thakis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#630291}