GitLab

(Apart from the dedicated GYP builders, of course).

This affects:

- chromium.fyi
  - Closure Compilation Linux
  - CrWinAsan
  - CrWinAsan(dll)
  - CrWinAsanCov
- chromium.lkgr
  - Win ASan Release Coverage
  - Win ASan Release Media
  - Win ASan Release
- chromium.mac
  - ios-simulator
- chromium.memory.full
  - Chromium Windows Builder (DrMemory x64)
  - Chromium Windows Builder (DrMemory)
- tryserver.chromium.linux
  - closure_compilation
- tryserver.chromium.mac
  - ios-simulator

Though the closure compilation builder doesn't really use GN or MB yet.

TBR=brettw@chromium.org
BUG=605318, 621708

Review-Url: https://codereview.chromium.org/2198693002
Cr-Commit-Position: refs/heads/master@{#408890}