c2_e2e_test: Release the output buffer if the frame is dropped.

The frames which arrived later than expected time are treated as the
dropped frames. The renderer side should drop them immediately. In the
E2E test, we should release the output buffer immediately to simulate
the real situation.

Bug: 155944233
Test: Run tast.arc.VideoDecodeAccelPerf.h264_2160p_30fps

Change-Id: Ia3ab69fed58f52e625c303b585fe616d79edabf5
(cherry picked from commit 2a73849fd901eb08ddccebbf1816f400ca6f7b31)