Adding test for SingleNalUnit mode

modules/video_coding/codecs/test/videoprocessor_integrationtest.h

Index: modules/video_coding/codecs/test/videoprocessor_integrationtest.h
diff --git a/modules/video_coding/codecs/test/videoprocessor_integrationtest.h b/modules/video_coding/codecs/test/videoprocessor_integrationtest.h
index 9831e483f22f8965c43dcdb527eec15bd6a338ae..d38391540b0abb6f2057648ee6f10f4880911218 100644
--- a/modules/video_coding/codecs/test/videoprocessor_integrationtest.h
+++ b/modules/video_coding/codecs/test/videoprocessor_integrationtest.h
@@ -71,6 +71,12 @@ struct QualityThresholds {
   double min_min_ssim;
 };
 
+struct BitstreamThresholds {
+  explicit BitstreamThresholds(size_t max_nalu_length)
+      : max_nalu_length(max_nalu_length) {}
+  size_t max_nalu_length;
+};
+
 // Should video files be saved persistently to disk for post-run visualization?
 struct VisualizationParams {
   bool save_encoded_ivf;
@@ -122,6 +128,7 @@ class VideoProcessorIntegrationTest : public testing::Test {
       const RateProfile& rate_profile,
       const std::vector<RateControlThresholds>* rc_thresholds,
       const QualityThresholds* quality_thresholds,
+      const BitstreamThresholds* bs_thresholds,
       const VisualizationParams* visualization_params);
 
   // Config.
@@ -192,6 +199,9 @@ class VideoProcessorIntegrationTest : public testing::Test {
       const std::vector<int>& num_dropped_frames,
       const std::vector<int>& num_spatial_resizes) const;
 
+  void VerifyBitstream(int frame_number,
+                       const BitstreamThresholds& bs_thresholds);
+
   // Codecs.
   std::unique_ptr<VideoEncoder> encoder_;
   std::unique_ptr<VideoDecoder> decoder_;