Use ArrayView in the IncomingRtcpPacket function.

The lowest level and some of the highest levels of this function are
already using ArrayView. Make this consistent throughout.
Use deprecation for the old API rather than deleting it, since upstream
may be using it.

Bug: webrtc:14870
Change-Id: If5e1a6e9802ecf7e8e3ec27befb5167ca9985517
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/291706
Commit-Queue: Harald Alvestrand <hta@webrtc.org>
Reviewed-by: Evan Shrubsole <eshr@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#39241}
diff --git a/modules/rtp_rtcp/source/rtp_rtcp_impl2.h b/modules/rtp_rtcp/source/rtp_rtcp_impl2.h
index e7a3ac0..b6071d9 100644
--- a/modules/rtp_rtcp/source/rtp_rtcp_impl2.h
+++ b/modules/rtp_rtcp/source/rtp_rtcp_impl2.h
@@ -66,8 +66,14 @@
   // Receiver part.
 
   // Called when we receive an RTCP packet.
-  void IncomingRtcpPacket(const uint8_t* incoming_packet,
-                          size_t incoming_packet_length) override;
+  [[deprecated("Use ArrayView version")]] void IncomingRtcpPacket(
+      const uint8_t* incoming_packet,
+      size_t incoming_packet_length) override {
+    IncomingRtcpPacket(
+        rtc::MakeArrayView(incoming_packet, incoming_packet_length));
+  }
+  void IncomingRtcpPacket(
+      rtc::ArrayView<const uint8_t> incoming_packet) override;
 
   void SetRemoteSSRC(uint32_t ssrc) override;