[PwdCheckAndroid] Add progress tracker to PasswordCheckManager

The progress tracker is responsible for counting the credentials
that have been processed by the check, as well as the number of
credentials that are still to be processed.

Since the bulk leak check tries to be as efficient as possible, it
performs a deduplication step before starting to check passwords. In
this step it canonicalizes each credential, and only processes the
combinations that are unique. Since this number likely does not match
the total number of saved passwords, the tracker updates the counts
with the number of saved passwords that share the same canonicalized
credential.

TBR=andzaytsev@google.com

Bug: 1102025, 1092444
Change-Id: I09dd04c0c563a70998e5a415956a619315d27656
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2363759
Commit-Queue: Ioana Pandele <ioanap@chromium.org>
Reviewed-by: Friedrich [CET] <fhorschig@chromium.org>
Reviewed-by: Jan Wilken Dörrie <jdoerrie@chromium.org>
Cr-Commit-Position: refs/heads/master@{#800164}