kiosk: Tighten no browser window restriction.

- Do not pop up file manager on volume mount;
- Watch browser open in kiosk session, log the opened url so that the code
  path could be fixed and close the just opened browser;

BUG=335272,331378

Review URL: https://codereview.chromium.org/135303011

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@245784 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 245784