cryptohome: Fix a regression with attestation initialization.

The EK public key is now cached before the TPM is owned. However, this
state should not be considered a ready-for-enrollment state.

BUG=chromium:473892
TEST=unit, manually tested attestation through enrollment

Change-Id: I0460bbbc6ebfa4f9e2346b4e4410ab964c899129
Previous-Reviewed-on: https://chromium-review.googlesource.com/264260
(cherry picked from commit 3db43d02172d268572c22bb7ebcb602a5f9d3834)
Reviewed-on: https://chromium-review.googlesource.com/264387
Reviewed-by: Darren Krahn <dkrahn@chromium.org>
Commit-Queue: Darren Krahn <dkrahn@chromium.org>
Tested-by: Darren Krahn <dkrahn@chromium.org>
1 file changed