Log time between network drops -- from online to offline.

Rewrite most of metrics_daemon. Convert to low-level D-Bus API -- this
simplifies the code a little and also allows us to catch the power
state signal. I still suspect we may be abusing D-Bus a little but it
seems to work.

snanda@ -- please review the power state code specifically.

TEST=tested on target platform and arm-generic builds

Review URL: http://codereview.chromium.org/1799001
6 files changed
tree: 900657ed6c2996e2c460ee51b7b58541478cad04
  1. metrics/