chromeos: Add pref for automated brightness increases.

DEPS

 # This file is used to manage the dependencies of the Chromium src repo. It is
 # used by gclient to determine what version of each dependency to check out, and
 # where.
 #
 # For more information, please refer to the official documentation:
 #   https://sites.google.com/a/chromium.org/dev/developers/how-tos/get-the-code
 #
 # When adding a new dependency, please update the top-level .gitignore file
 # to list the dependency's destination directory.
 #
@@ skipping 402 matching lines @@
      Var('chromium_git') + '/chromium/deps/xdg-utils.git' + '@' + 'd80274d5869b17b8c9067a1022e4416ee7ed5e0d',
 
     'src/third_party/swig/linux':
      Var('chromium_git') + '/chromium/deps/swig/linux.git' + '@' + '866b8e0e0e0cfe99ebe608260030916ca0c3f92d',
 
     'src/third_party/lss':
       Var('chromium_git') + '/external/linux-syscall-support/lss.git' + '@' + Var('lss_revision'),
 
     # For Linux and Chromium OS.
     'src/third_party/cros_system_api':
-     Var('chromium_git') + '/chromiumos/platform/system_api.git' + '@' + 'eb5b6c3152ddf0b8212cc35d384c231e20aaeb62',
+     Var('chromium_git') + '/chromiumos/platform/system_api.git' + '@' + '7678688b4405325d32fdfb45064128b9accb9a71',
 
     # Note that this is different from Android's freetype repo.
     'src/third_party/freetype2/src':
      Var('chromium_git') + '/chromium/src/third_party/freetype2.git' + '@' + '495a23fce9cd125f715dc20643d14fed226d76ac',
 
     # Build tools for Chrome OS.
     'src/third_party/chromite':
      Var('chromium_git') + '/chromiumos/chromite.git' + '@' + 'c1bb274a82c13f76c3d8560808423605bfd84d76',
 
     # Dependency of chromite.git.
@@ skipping 361 matching lines @@
     # corresponding .py files have already been deleted.
     'name': 'remove_stale_pyc_files',
     'pattern': 'src/tools/.*\\.py',
     'action': [
         'python',
         'src/tools/remove_stale_pyc_files.py',
         'src/tools',
     ],
   },
 ]