Implement h.265 parameter sets tracker.

RTP spec for H.265 requires parameter sets to be included in IRAP
pictures. This CL adds the helper for rtc_video_encoder to deliver
encoded bitstream for all VEA outputs.

This CL is based on Jianlin's CL https://crrev.com/c/5307256

.

Co-authored-by: Jianlin Qiu <jianlin.qiu@intel.com>

Bug: webrtc:13485
Change-Id: I6cfba23c957fdc90deb66b7e580c8a20cd22aef3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5335904


Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Reviewed-by: Dan Sanders <sandersd@chromium.org>
Commit-Queue: Jianlin Qiu <jianlin.qiu@intel.com>
Cr-Commit-Position: refs/heads/main@{#1277264}