Merge from master branch of Widevine repo of http://go/wvgerrit/66066
Merge from oemcrypto-v15 branch of Widevine repo of http://go/wvgerrit/63628
The error code OEMCrypto_KEY_NOT_LOADED is redundant with
OEMCrypto_ERROR_NO_CONTENT_KEY and OEMCrypto_KEY_NOT_ENTITLED. The
function LoadEntitledContentKey should return KEY_NOT_ENTITLED if it
does not find the corresponding entitlement key in its key table. All
other functions that do not find a key id in the key table should
return OEMCrypto_ERROR_NO_CONTENT_KEY. This includes QueryKeyControl,
SelectKey, and RefreshKeys.
Test: unit tests
Test: tested as part of http://go/ag/5501993
Bug: 115574797
Change-Id: Ida2111f32e331b99f3f0c77fa404a42654d0870c
ef067572bc