In order to allow this code to properly operate for all Chromium and Chrome flavors (e.g. Stable, Beta, Canary etc.) it is important to allow for different source names for the Event Logger.

The default behavior of SYSLOG now is equivalent to a LOG unless
SetEventSourceName is called at which point the function can start
logging to the Event Log as well.

For Branded Chrome build the event source stays Chrome for the Stable channel and will have the proper appendix for the various other channels whereas for non-branded build it will be Chromium.

BUG=668397
TEST=none

Review-Url: https://codereview.chromium.org/2530163002
Cr-Commit-Position: refs/heads/master@{#436994}