Ensure address bar is reset after a redirect turns into a download.

      BUG=83031
TEST=NavigationControllerTest.LoadURL_RedirectAbortCancelsPending

Review URL: http://codereview.chromium.org/6993037

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@88886 0039d316-1c4b-4281-b951-d872f2087c98