[tooltip text] Bookmark folder button tooltip not showing fix

Ths CL fixes a bug where the tooltip text for bookmark folders was not
showing. We simply now update the tooltip text when we create the
button.

Previously the tooltip text would get updated when `OnTextChanged` was
called but this doesn't get triggered on creation.

Fixed: 452607238
Change-Id: I0814a1502528a0c9044a788712918bb0f8c8bf78
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7055444
Reviewed-by: Benjamin Beaudry <benjamin.beaudry@microsoft.com>
Auto-Submit: Javier Contreras <javiercon@microsoft.com>
Reviewed-by: Avi Drissman <avi@chromium.org>
Commit-Queue: Avi Drissman <avi@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1532027}