Move security token PIN enums to //chromeos

Move the enums out from the SecurityTokenPinDialogHost interface (that
is defined at //chrome/browser/chromeos) into a separate header under
//chromeos.

This allows to reuse these enums in //ash.

Bug: 983103
Change-Id: Ide120d445ad235e93888886d4ae5d7707304ad7f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1744147
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Commit-Queue: Maksim Ivanov <emaxx@chromium.org>
Cr-Commit-Position: refs/heads/master@{#685198}
8 files changed