Reduce number of DefaultNumberOfTemporalLayers() calls

Bug: none
Change-Id: Ie177734dd885d179ba9c9d44f63d106e8fcb8e29
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/329980
Reviewed-by: Erik Språng <sprang@webrtc.org>
Commit-Queue: Sergey Silkin <ssilkin@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#41334}
diff --git a/video/config/simulcast.cc b/video/config/simulcast.cc
index 2bd4ac0..7a78ef8 100644
--- a/video/config/simulcast.cc
+++ b/video/config/simulcast.cc
@@ -350,10 +350,9 @@
     bool base_heavy_tl3_rate_alloc,
     const webrtc::FieldTrialsView& trials) {
   std::vector<webrtc::VideoStream> layers(layer_count);
-
   const bool enable_lowres_bitrate_interpolation =
       EnableLowresBitrateInterpolation(trials);
-
+  const int num_temporal_layers = DefaultNumberOfTemporalLayers(trials);
   // Format width and height has to be divisible by |2 ^ num_simulcast_layers -
   // 1|.
   width = NormalizeSimulcastSize(width, layer_count);
@@ -366,7 +365,7 @@
     // TODO(pbos): Fill actual temporal-layer bitrate thresholds.
     layers[s].max_qp = max_qp;
     layers[s].num_temporal_layers =
-        temporal_layers_supported ? DefaultNumberOfTemporalLayers(trials) : 1;
+        temporal_layers_supported ? num_temporal_layers : 1;
     layers[s].max_bitrate_bps =
         FindSimulcastMaxBitrate(width, height,
                                 enable_lowres_bitrate_interpolation)
@@ -375,7 +374,6 @@
         FindSimulcastTargetBitrate(width, height,
                                    enable_lowres_bitrate_interpolation)
             .bps();
-    int num_temporal_layers = DefaultNumberOfTemporalLayers(trials);
     if (s == 0) {
       // If alternative temporal rate allocation is selected, adjust the
       // bitrate of the lowest simulcast stream so that absolute bitrate for