message: Ensure release bots run with dchecks off.
  Follow-up of
  inspired by V8's crrev.com/c/3048180.
  Cr-Commit-Position: refs/heads/master@{#34542}
diff: 'gn_args': 'is_clang=true',
  },
  + # This mixin also sets 'dcheck_always_on=true' to ensure Chromium's
  + # GN files (e.g. things in //build, etc..) agree with the value of
  + # 'rtc_dcheck_always_on' when they read 'dcheck_always_on'.
  + # See crbug.com/1231890#c9 for more info.
  'rtc_dcheck_always_on': {
  - 'gn_args': 'rtc_dcheck_always_on=true',
  + 'gn_args': 'rtc_dcheck_always_on=true dcheck_always_on=true',
  },
  'debug': {
  'gn_args': 'optimize_for_fuzzing=true',
  },
  - 'pure_release_bot': {
  - 'mixins': ['release', 'goma'],
  - },
  -
  'release': {
  - 'gn_args': 'is_debug=false',
  + 'gn_args': 'is_debug=false dcheck_always_on=false',
  },
  + # The 'pure_release_bot' configuration is for release bots that are doing a
  + # 100% release build without DCHECKs while 'release_bot' is a partial
  + # release configs since both `rtc_dcheck_always_on` and `dcheck_always_on`
  + # are set to true.
  + 'pure_release_bot': {
  + 'mixins': ['release', 'goma'],
  + },
  'release_bot': {
  'mixins': ['pure_release_bot', 'rtc_dcheck_always_on'],
  },
  