This merges the following changes from the Widevine CDM repository:
1a72a7e Combine utility code into single library on Android
Combines several previously-separate files into a static library,
libcdm_utils, so that it can easily be used by both CDM and
OEMCrypto.
8c4d04d Install Keybox
If the keybox has not been installed, install it from
/factory/wv.keys.
Bug: 9972451
Change-Id: I8688ecd0adcf321e0c7d0faf55dd10f3910c12ec