Save and restore the options window position instead of always centering the window.

BUG=34644
TEST=Open options window, move and close the window, re-open and ensure position is saved. 
Contributed by Steven Pennington <spenn@engr.uvic.ca>

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@57086 0039d316-1c4b-4281-b951-d872f2087c98