Filter out the non-RTP packet in RtpTransport.
Filter out the non-RTP packet in RtpTransport.

Bug: b/77547687
Change-Id: Id13b4f918208b76040bfbef1ec771f2a42831519
Reviewed-on: https://webrtc-review.googlesource.com/66602
Commit-Queue: Zhi Huang <64514bc03b49e67cfb75da60b665f8d8aefa50ca@webrtc.org>
Reviewed-by: Steve Anton <93f73658da16553b94c040887a439a155812e54e@webrtc.org>
Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#22714}
ShiftMediaProject/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc