GitLab

to be within metrics code

MetricsReportingEnabled checkbox changed code refactored for not-chromeos:
-prefs removed from HTML
-Handler and callback functions added to core_options_handler
-Major refactoring in metrics_reporting_state
-Simple histogram added in metrics_reporting_state without distinguishing the source of the change
-browser_options_handler changed to handle new way of forcing company policies of disabling the checkbox

BUG=401233

NOPRESUBMIT=true
R=asvitkine@chromium.org

Review URL: https://codereview.chromium.org/506663003

Patch from Gayane Petrosyan <gayane@chromium.org>.

Cr-Commit-Position: refs/heads/master@{#295124}