Given a ContentProtection schemeIdUri, returns the DrmKeySystem it represents.
Not all scheme ids will match to a DrmKeySystem. If none are matched, null is returned.
For example, CENC 'urn:mpeg:dash:mp4protection:2011' has no key system and shouldn't be used
to create a key session.
Given a ContentProtection schemeIdUri, returns the DrmKeySystem it represents. Not all scheme ids will match to a DrmKeySystem. If none are matched, null is returned. For example, CENC 'urn:mpeg:dash:mp4protection:2011' has no key system and shouldn't be used to create a key session.