Merge "CCodec: don't release all references at flush" am: d22cd941c8 am: 9db4c91fd4 am: 5fea7f7e74

Original change: https://android-review.googlesource.com/c/platform/frameworks/av/+/1554927

Change-Id: Ieaaf78b88f6e329f3baf5f676cf47eb9380ee9af