Unittest fix. Need to put usersubmitted = true for unittests.

BUG=51727

Review URL: http://codereview.chromium.org/3151006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@55632 0039d316-1c4b-4281-b951-d872f2087c98
  AutocompleteHistoryManagerTest()
      : ui_thread_(ChromeThread::UI, &message_loop_) {
  }

  AutocompleteHistoryManagerTest()
      : ui_thread_(ChromeThread::UI, &message_loop_) {
  }
