Remove sync-related login code on OS_CHROMEOS platforms.
ChromeOS doesn't need the sync login code - in fact, it's actively bad to have
this code in there because it keeps getting triggered through various bugs. As
an interim measure, this CL #if-outs the code on chromeos platforms. Once we
have removed the non-web-based signin code, we can look at the remaining code
and decide whether it is worth refactoring this into platform-specific classes.
BUG=236005
R=arv@chromium.org, rogerta@chromium.org
Review URL: https://codereview.chromium.org/
14696017
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@200475 0039d316-1c4b-4281-b951-d872f2087c98