[FWS] Improve behavior when starting with no network

Before this cl, FloatingWorkspaceService could restore the most recent
local desk when offline. This was not intentional and was caused by the
fact that Sync may report download status as "up to date" when offline.
Now we also monitor the upload state and wait for it to switch to
"active" before we start restoring.

Additionally, this cl removes the logic to cancel restoration after 30
seconds of waiting. We also remove the "restore after error"
notification which was shown in that case. Notifications are about to be
replaced by the new UI which allows to wait until the user decides to
cancel the restoration manually. This explains a lot of removed tests.

Bug: b:416723935
Test: FloatingWorkspaceServiceV2Test.ConnectAfterNotHavingNetworkInitially
Change-Id: I0eac0dc24cf16ed119c0c286b345a7c039df1423
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6532706
Commit-Queue: Andrey Davydov <andreydav@google.com>
Reviewed-by: Michael Slutskii <slutskii@google.com>
Cr-Commit-Position: refs/heads/main@{#1458826}