As PowerUsageMonitor is only reporting UMA data and nothing else, then PowerUsageMonitor can be started without checking UMA bit. The existing metrics service will take care of not uploading the data if The UMA bit is off.

Currently the check is there so that PowerUsageMonitor is not uselessly working in cases when the data will not be uploaded anyway. However in general we prefer to avoid such checks because enabling UMA shouldn't give users 'slower' Chrome. 

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2d74e1b7211331a5ae569190e5ab7725f47afd0f

commit 2d74e1b7211331a5ae569190e5ab7725f47afd0f
Author: gayane <gayane@chromium.org>
Date: Tue Apr 05 16:12:58 2016

Start PowerUsageMonitor unconditionally from UMA bit.

As PowerUsageMonitor is only reporting UMA data and nothing else, then PowerUsageMonitor can be started without checking UMA bit. The existing metrics service will take care of not uploading the data if The UMA bit is off.

Currently the check is there so that PowerUsageMonitor is not uselessly working in cases when the data will not be uploaded anyway. However in general we prefer to avoid such checks because enabling UMA shouldn't give users 'slower' Chrome.

BUG= 600398 

Review URL: https://codereview.chromium.org/1855223003

Cr-Commit-Position: refs/heads/master@{#385183}

[modify] https://crrev.com/2d74e1b7211331a5ae569190e5ab7725f47afd0f/chrome/browser/chrome_browser_main.cc