chromeos: Bump system_api dependency to a6b76c4e.

I'm doing this to pick up power_manager::kSetIsProjectingMethod.

BUG=chromium-os:31672
TEST=built Chrome for ChromeOS


Review URL: https://chromiumcodereview.appspot.com/10548010

git-svn-id: http://src.chromium.org/svn/trunk/src/tools/cros.DEPS@141890 4ff67af0-8c30-449e-8e8b-ad334ec8d88c
1 file changed
tree: 50ebd00ea032d036f117dd39b87630da8011e744
  1. DEPS
  2. README