* The Usage APIs return usage reports from either L1 or L3 (if available).
* Correction to when usage reports are saved. In addition to other events
they are now saved when keys are loaded, usage reports are released and soon
after first decryption and periodically (60 seconds) after that,
if decryption takes place.
* Usage reports now get deleted on an unprovision request.
* Policy timer is now started when offline licenses are restored.
* Usage session is now released, when a usage response is received.
* Usage tests ahev been enabled.
* Added CDM extended duration (integration) tests to test usage reporting
and querying. These need to be run manually as they take a while (currently
half an hour).
b/15592374
[ Merge of https://widevine-internal-review.googlesource.com/#/c/10800
from the Widevine CDM repo ]
Change-Id: Ia817e03ebbe880e08ba7b4a235ecb82b3ff35fbf