Birch: Switch to open tab when available

When a recent tab birch item is opened, prefer to switch to an
existing tab if one with the same URL is already open. When one is not
already open, then a new tab will be opened.

Bug: b/330384242
Change-Id: I252e966ed7db111ec029a0ff09065fca0074331f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5420467


Commit-Queue: Matthew Mourgos <mmourgos@chromium.org>
Reviewed-by: James Cook <jamescook@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1282185}