Revert^2 "VP9: Synthesize CSD from frame header"

44ad2bf9

Relands commits in /q/submissionid:2953128-vp9_csd_synthesis.

Reason for revert: The encoder tests have been modified to now
accept the synthesized VP9 CSD in aosp/3019090.

Test: atest android.mediav2.cts.DecoderColorAspectsTest#testColorAspects
Bug: 295804596

Change-Id: Iad5c9c698615424b2ebe854d82e94b07f3646e64