[UPMLocalPwd] Check that the ContainerView can be found by ID

The FragmentTransaction that sets the Fragment on the sheet should not
start if the FragmentContainerView is not there.

It could still happen that the sheet closes right after this check and
there is no place for the Fragment anymore. Such crashes will now be
uploaded to the dashboard without crashing. This could help with further
debugging.

commit() is replaced with commitNow() in hope to get better logs if
the crash repeats. The stack trace should then include the migration
warning code.

The onShowEventListener should only be called if committing the
transaction did not throw an exception. This is because the warning
shouldn't be marked as shown in the stored Chrome pref if it failed
to show the content.

Bug: 1468464
Change-Id: I1a799b4c5daf872d60b5196115927d6298033553
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4774579
Reviewed-by: Friedrich Horschig <fhorschig@chromium.org>
Reviewed-by: Ioana Pandele <ioanap@chromium.org>
Code-Coverage: findit-for-me@appspot.gserviceaccount.com <findit-for-me@appspot.gserviceaccount.com>
Reviewed-by: Vasilii Sukhanov <vasilii@chromium.org>
Commit-Queue: Ioana Pandele <ioanap@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1183124}