chromeos: Remove dead power manager code.

chromeos: Remove dead power manager code.

This removes the OutputObserver class, which used to listen
for ScreenPowerSetSignal D-Bus signals from powerd and pass
the requests on to OutputConfigurator.  This is now handled
by DisplayPowerServiceProvider, which serves as an endpoint
for SetDisplayPower method calls.

It also removes the timestamp argument from
HandleUserActivity method calls to powerd.  powerd no longer
uses (or reads, for that matter) the argument.

BUG=chromium:221391
TBR=ben@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=189809

[stevenjb, 2013-03-21 18:32:41]

lgtm

[commit-bot: I haz the power, 2013-03-21 18:55:44]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/derat@chromium.org/12992004/1

[commit-bot: I haz the power, 2013-03-21 18:55:50]

Presubmit check for 12992004-1 failed and returned exit status 1.

INFO:root:Found 8 file(s).

Running presubmit commit checks ...
Running /b/commit-queue/workdir/chromium/PRESUBMIT.py
Running /b/commit-queue/workdir/chromium/chrome/PRESUBMIT.py

** Presubmit ERRORS **
Missing LGTM from an OWNER for these files:
    chrome/chrome_browser_chromeos.gypi

Presubmit checks took 1.0s to calculate.

Was the presubmit check useful? Please send feedback & hate mail to
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[Daniel Erat, 2013-03-21 19:10:21]

TBR ben for chrome/chrome_browser_chromeos.gypi

[commit-bot: I haz the power, 2013-03-21 19:38:14]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/derat@chromium.org/12992004/1

[commit-bot: I haz the power, 2013-03-21 22:11:40]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/derat@chromium.org/12992004/21001

[Daniel Erat, 2013-03-22 15:02:50]

Committed patchset #3 manually as r189809 (presubmit successful).