[Uno-D] Create IPH bubble for web signout on Uno

Screenshot:
https://screenshot.googleplex.com/5XPvr3pNZCJ8jLu.png

Preview:
https://screencast.googleplex.com/cast/NjE4MTI0MDIxMzM0MDE2MHw5ODQ5YjkzOS1hNw

PRD:
https://docs.google.com/document/d/1Wq6j0fLSBuHGqHQXo9pKQaghm7RB_2D1LSRrg8W3GqE/edit?resourcekey=0-radQT_JsSI8E30Jt-ld6xw&tab=t.0#bookmark=id.i2wgu44t6i8h

Bug: b/319402139
Change-Id: I7e99390e60d8041d64c1e80120bf410272bee79c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5377876


Reviewed-by: Dana Fried <dfried@chromium.org>
Commit-Queue: Gabriel Oliveira <gabolvr@google.com>
Reviewed-by: Ryan Sultanem <rsult@google.com>
Cr-Commit-Position: refs/heads/main@{#1289246}