[ Merge of https://go/wvgerrit/17055 ]
There are a few bugs that need to be addressed to get HLS to work.
* Content ID in json init data is base64 encoded and needs to be decoded
before being added to the WidevineCencHeader proto.
* Protection scheme was not set in the WidevineCencHeader proto.
* HLS initialization data should be sent as a CENC content identification
in a license request.
b/20630275
Change-Id: Ie0ac33ac061931df6f26c0afbf3e62e5d01e5041