In a renewal message, in order to extend the duration, the server sdk
sends back a single key in the key container. Earlier the key was of type
CONTENT and only contained a key control block. No id, key data or
iv information were supplied. After a recent server sdk update
the key type in the renewal message has been changed to KEY_CONTROL.
This change enables the client to process the updated renewal message.
bug: 8736545
Merge of https://widevine-internal-review.googlesource.com/#/c/5434/
from Widevine CDM repository
Change-Id: Ia9f3620b86460278285fddee57ee923e269de7c1