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We are replacing tpm status APis by cryptohome with tpm manager service.

Though the change to the workflow is implemented UserSessionManager is
supposed to operate almost the same way, before and after this CL.
Below the behavioral changes are highlighted:

1. TpmIsBeingOwned is removed as a factor from the state machine.
TpmIsBeingOwned is no longer supported and always returns `false` now.
Removing it is a trivial change.
2. As for execution order, `PrepareFinalizeProfile()` is separated
totally from the preparation of TPM device. The justification comes from
the fact that `CryptohomeClient::CanAttemptOwnership()` only triggers
TPM initialization by tpm manager w/o waiting for it to complete; it
doesn't make sense to just wait for a trigger w/o checking its result.
Clearing owner password is in best effort and the result is not checked
even in cases where any remaining owner password dependencies stops the
password from being cleared.
3. TPM status checking is made asynchronous after this CL to make sure
UI thread doesn't get blocked.
4. Upon failure of calling tpm_manager, `DCHECK` is replaced by logging
error message. It doesn't make sense to just crash upon the error, and
in production it doesn't make any difference anyway.

BUG=b:172748724
BUG=b:172775884
TEST=unit_tests (filter: *UserSessionManager*)
TEST=browser_tests (filter: *ExistingUserController*)
TEST=asan + msan builder trybot passes.
TEST= perform first login, check if the password exists/gets wiped
before/after the login.

Change-Id: I66c5ef3faae8c78d9f2cb304ccf59ca7a8f80c01
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2560087
Commit-Queue: Leo Lai <cylai@google.com>
Reviewed-by: Achuith Bhandarkar <achuith@chromium.org>
Cr-Commit-Position: refs/heads/master@{#836026}