buffet: Add ability to add commands via buffet_client

Implemented "AddCommand" parameter in buffet_client that queues
a GCD command in buffet daemon.

BUG=chromium:412583
TEST=FEATURES=test emerge-link buffet

Change-Id: Ie5a6561efc8675ba5fb234c1151a0f1dbda39e5d
Reviewed-on: https://chromium-review.googlesource.com/217829
Reviewed-by: Christopher Wiley <wiley@chromium.org>
Reviewed-by: Anton Muhin <antonm@chromium.org>
Commit-Queue: Alex Vakulenko <avakulenko@chromium.org>
Tested-by: Alex Vakulenko <avakulenko@chromium.org>
5 files changed
tree: 47d95722eebb09cf107c5fc1e430cb19c1686dde
  1. buffet/