Adding API to read/write uncompressed frame header bits.

The API is not final yet and can be changed. Actual layout of
uncompressed frame part will be finalized later. Right now moving
clr_type, error_resilient_mode, refresh_frame_context,
frame_parallel_decoding_mode from first compressed partition to
uncompressed frame part.

Change-Id: I3afc5d4ea92c5a114f4c3d88f96858cccc15b76e