[IceBreaker&Dasherless] Add profile GUID pre-generation.

Add the options to pre-generate profile GUID before it's created in profile ID service and to calculate profile ID with a given profile GUID.

Current use case: Profile registration occurs before profile creation in the OIDC flow, because the registration process also acts as validation process for the OIDC authentication results.
The flow needs to use the same profile ID in this first registration call, and in the first policy fetch call after the profile is created. Otherwise, DM server will create two separate entries for the same profile, and one of them is obsolete.

Bug: 326188539
Change-Id: I975a1e4b5a95faaf290b2ab9948c7a0847da367b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5331522
Commit-Queue: Zonghan Xu <xzonghan@chromium.org>
Reviewed-by: Owen Min <zmin@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1304645}