Reland "Disable frame dropping from codec settings."

This is a reland of 34aba3cefd9519a8da6700f725a9e2d99ee2ef61

Original change's description:
> Disable frame dropping from codec settings.
>
> This was broken in https://webrtc-review.googlesource.com/c/src/+/99062/
>
> Bug: webrtc:9734
> Change-Id: Ibce41a732cb2e943354c87fbb05be0dd218acf27
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/242366
> Reviewed-by: Erik Språng <sprang@webrtc.org>
> Commit-Queue: Sergey Silkin <ssilkin@webrtc.org>
> Cr-Commit-Position: refs/heads/main@{#35568}

Bug: webrtc:9734
Change-Id: I84efcab334b99aa08b07cc5e891681bfd5b2865f
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/247182
Reviewed-by: Erik Språng <sprang@webrtc.org>
Commit-Queue: Sergey Silkin <ssilkin@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#35712}
diff --git a/modules/video_coding/codecs/vp8/libvpx_vp8_encoder.cc b/modules/video_coding/codecs/vp8/libvpx_vp8_encoder.cc
index 17220b1..a613be4 100644
--- a/modules/video_coding/codecs/vp8/libvpx_vp8_encoder.cc
+++ b/modules/video_coding/codecs/vp8/libvpx_vp8_encoder.cc
@@ -856,16 +856,19 @@
 }
 
 uint32_t LibvpxVp8Encoder::FrameDropThreshold(size_t spatial_idx) const {
-  bool enable_frame_dropping = codec_.VP8().frameDroppingOn;
+  if (!codec_.VP8().frameDroppingOn) {
+    return 0;
+  }
+
   // If temporal layers are used, they get to override the frame dropping
   // setting, as eg. ScreenshareLayers does not work as intended with frame
   // dropping on and DefaultTemporalLayers will have performance issues with
   // frame dropping off.
   RTC_DCHECK(frame_buffer_controller_);
   RTC_DCHECK_LT(spatial_idx, frame_buffer_controller_->StreamCount());
-  enable_frame_dropping =
-      frame_buffer_controller_->SupportsEncoderFrameDropping(spatial_idx);
-  return enable_frame_dropping ? 30 : 0;
+  return frame_buffer_controller_->SupportsEncoderFrameDropping(spatial_idx)
+             ? 30
+             : 0;
 }
 
 size_t LibvpxVp8Encoder::SteadyStateSize(int sid, int tid) {
diff --git a/modules/video_coding/codecs/vp8/test/vp8_impl_unittest.cc b/modules/video_coding/codecs/vp8/test/vp8_impl_unittest.cc
index 2e2597e..c257edd 100644
--- a/modules/video_coding/codecs/vp8/test/vp8_impl_unittest.cc
+++ b/modules/video_coding/codecs/vp8/test/vp8_impl_unittest.cc
@@ -76,9 +76,6 @@
     webrtc::test::CodecSettings(kVideoCodecVP8, codec_settings);
     codec_settings->width = kWidth;
     codec_settings->height = kHeight;
-    codec_settings->VP8()->denoisingOn = true;
-    codec_settings->VP8()->frameDroppingOn = false;
-    codec_settings->VP8()->automaticResizeOn = false;
     codec_settings->VP8()->complexity = VideoCodecComplexity::kComplexityNormal;
   }
 
@@ -408,7 +405,6 @@
 }
 
 TEST_F(TestVp8Impl, ScalingDisabledIfAutomaticResizeOff) {
-  codec_settings_.VP8()->frameDroppingOn = true;
   codec_settings_.VP8()->automaticResizeOn = false;
   EXPECT_EQ(WEBRTC_VIDEO_CODEC_OK,
             encoder_->InitEncode(&codec_settings_, kSettings));
@@ -419,7 +415,6 @@
 }
 
 TEST_F(TestVp8Impl, ScalingEnabledIfAutomaticResizeOn) {
-  codec_settings_.VP8()->frameDroppingOn = true;
   codec_settings_.VP8()->automaticResizeOn = true;
   EXPECT_EQ(WEBRTC_VIDEO_CODEC_OK,
             encoder_->InitEncode(&codec_settings_, kSettings));