This allows a DRM client to open a locally-cached file on behalf of the
DRM server so the DRM server no longer requires the sdcard_r permission
to access the file's metadata. Specifically, this adds an optional
attribute FileDescriptorKey to the DrmInfoRequest.
This change is dependent on this Widevine CL:
https://widevine-internal-review.googlesource.com/#/c/1330/
Relevant bug reports:
bug: 6426185
Change-Id: Ia7bcb2455c7a55fa4c7c7061de4d672957c7ac0a
Includes Widevine libraries Version 4.5.0.7809
Also fixed samplePlayer's MediaCodec mode not running and
WVDrmInfoRequestStatusKey returning incorrect value.
Change-Id: Ibcc6d313790670a908ada93be80d6bf55a67b4ed
related-to-bug: 6929628
related-to-bug: 6833718
related-to-bug: 6889322