Merge "Add tests to validate key length for clearkey plugin. am: c312e21b5e  -s ours am: 4a9b599f9a  -s ours" into oc-mr1-dev am: 21ac066637  -s ours
am: 656edbfa96  -s ours

Change-Id: I5396ad646b6dc941587c0979f8465804c736efca