Reland "Populate the GFD-00 for H264 and generic codecs."

This is a reland of d3c6f9ccffe88749fde8bc1320baa1fe2db15b6b

Original change's description:
> Populate the GFD-00 for H264 and generic codecs.
> 
> Bug: none
> Change-Id: I368eb38740314280db87aaf8e179e9bd0fc20c3c
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/103502
> Commit-Queue: Philip Eliasson <philipel@webrtc.org>
> Reviewed-by: Niels Moller <nisse@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#28272}

Bug: none
Change-Id: Ic02590e5328783969d5480a8f413986ef7055f8e
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/142168
Reviewed-by: Philip Eliasson <philipel@webrtc.org>
Reviewed-by: Niels Moller <nisse@webrtc.org>
Commit-Queue: Philip Eliasson <philipel@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#28289}

call/rtp_payload_params.cc

diff --git a/call/rtp_payload_params.cc b/call/rtp_payload_params.cc
index 84ca65f..5990123 100644
--- a/call/rtp_payload_params.cc
+++ b/call/rtp_payload_params.cc
@@ -256,7 +256,7 @@
                                   RTPVideoHeader* rtp_video_header) {
   switch (rtp_video_header->codec) {
     case VideoCodecType::kVideoCodecGeneric:
-      // TODO(philipel): Implement generic codec to new generic descriptor.
+      GenericToGeneric(frame_id, is_keyframe, rtp_video_header);
       return;
     case VideoCodecType::kVideoCodecVP8:
       if (codec_specific_info) {
@@ -268,13 +268,90 @@
       // TODO(philipel): Implement VP9 to new generic descriptor.
       return;
     case VideoCodecType::kVideoCodecH264:
-      // TODO(philipel): Implement H264 to new generic descriptor.
+      if (codec_specific_info) {
+        H264ToGeneric(codec_specific_info->codecSpecific.H264, frame_id,
+                      is_keyframe, rtp_video_header);
+      }
+      return;
     case VideoCodecType::kVideoCodecMultiplex:
       return;
   }
   RTC_NOTREACHED() << "Unsupported codec.";
 }
 
+void RtpPayloadParams::GenericToGeneric(int64_t shared_frame_id,
+                                        bool is_keyframe,
+                                        RTPVideoHeader* rtp_video_header) {
+  RTPVideoHeader::GenericDescriptorInfo& generic =
+      rtp_video_header->generic.emplace();
+
+  generic.frame_id = shared_frame_id;
+
+  if (is_keyframe) {
+    last_shared_frame_id_[0].fill(-1);
+  } else {
+    int64_t frame_id = last_shared_frame_id_[0][0];
+    RTC_DCHECK_NE(frame_id, -1);
+    RTC_DCHECK_LT(frame_id, shared_frame_id);
+    generic.dependencies.push_back(frame_id);
+  }
+
+  last_shared_frame_id_[0][0] = shared_frame_id;
+}
+
+void RtpPayloadParams::H264ToGeneric(const CodecSpecificInfoH264& h264_info,
+                                     int64_t shared_frame_id,
+                                     bool is_keyframe,
+                                     RTPVideoHeader* rtp_video_header) {
+  const int temporal_index =
+      h264_info.temporal_idx != kNoTemporalIdx ? h264_info.temporal_idx : 0;
+
+  if (temporal_index >= RtpGenericFrameDescriptor::kMaxTemporalLayers) {
+    RTC_LOG(LS_WARNING) << "Temporal and/or spatial index is too high to be "
+                           "used with generic frame descriptor.";
+    return;
+  }
+
+  RTPVideoHeader::GenericDescriptorInfo& generic =
+      rtp_video_header->generic.emplace();
+
+  generic.frame_id = shared_frame_id;
+  generic.temporal_index = temporal_index;
+
+  if (is_keyframe) {
+    RTC_DCHECK_EQ(temporal_index, 0);
+    last_shared_frame_id_[/*spatial index*/ 0].fill(-1);
+    last_shared_frame_id_[/*spatial index*/ 0][temporal_index] =
+        shared_frame_id;
+    return;
+  }
+
+  if (h264_info.base_layer_sync) {
+    int64_t tl0_frame_id = last_shared_frame_id_[/*spatial index*/ 0][0];
+
+    for (int i = 1; i < RtpGenericFrameDescriptor::kMaxTemporalLayers; ++i) {
+      if (last_shared_frame_id_[/*spatial index*/ 0][i] < tl0_frame_id) {
+        last_shared_frame_id_[/*spatial index*/ 0][i] = -1;
+      }
+    }
+
+    RTC_DCHECK_GE(tl0_frame_id, 0);
+    RTC_DCHECK_LT(tl0_frame_id, shared_frame_id);
+    generic.dependencies.push_back(tl0_frame_id);
+  } else {
+    for (int i = 0; i <= temporal_index; ++i) {
+      int64_t frame_id = last_shared_frame_id_[/*spatial index*/ 0][i];
+
+      if (frame_id != -1) {
+        RTC_DCHECK_LT(frame_id, shared_frame_id);
+        generic.dependencies.push_back(frame_id);
+      }
+    }
+  }
+
+  last_shared_frame_id_[/*spatial_index*/ 0][temporal_index] = shared_frame_id;
+}
+
 void RtpPayloadParams::Vp8ToGeneric(const CodecSpecificInfoVP8& vp8_info,
                                     int64_t shared_frame_id,
                                     bool is_keyframe,