message: Add bionic mb builder config
  No-Try: True
  Cr-Commit-Position: refs/heads/master@{#34397}
diff: 'Perf Android64 (M Nexus5X)': 'release_bot_x64',
  'Perf Android64 (O Pixel2)': 'release_bot_x64',
  'Perf Linux Trusty': 'release_bot_x64',
  + 'Perf Linux Bionic': 'release_bot_x64',
  'Perf Mac 10.11': 'release_bot_x64',
  'Perf Win7': 'release_bot_x64',
  },
  