Disable "undo" snackbar if closing tab with peripheral button (2/2)

This CL is a follow-up to  https://crrev.com/c/6505981, where the "undo"
snackbar was disabled when there were multiple open tabs and a tab was
closed with a peripheral button.

In this CL, we handle the case where there is only one open tab to
close.

Bug: 375468032
Change-Id: If41b92c269e944103a19d22ba1f41c326f5f9250
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6514489
Reviewed-by: Zhe Li <zheliooo@google.com>
Reviewed-by: Neil Coronado <nemco@google.com>
Commit-Queue: Linyu He <linyuh@google.com>
Cr-Commit-Position: refs/heads/main@{#1456070}