Add profiles to wrench menu

This change adds a profile menu to the wrench menu.

If the user has one profile then the wrench menu looks like this:
  Wrench Menu >
    ...
    Downloads
    -------
    New Browsing Profile...
    -------
    ...

If the user has two or more profile then the wrench menu looks like this:
   Wrench Menu >
    ...
    Downloads
    -------
    Browsing Profiles >
       Profile 1
       Profile 2
       --------
       New Browsing Profile...
    -------
    ...

BUG=None
TEST=None
Review URL: http://codereview.chromium.org/7138002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@88942 0039d316-1c4b-4281-b951-d872f2087c98