Move PasswordManagerMetricsUtil into PasswordManager component.

BUG=334647
TBR=thakis

Review URL: https://codereview.chromium.org/156713003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@249708 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 249708