Piggybacking simulcast id and ALR experiment id into video content type extension.

webrtc/video/end_to_end_tests.cc

Index: webrtc/video/end_to_end_tests.cc
diff --git a/webrtc/video/end_to_end_tests.cc b/webrtc/video/end_to_end_tests.cc
index 106b5137123100c11b18d6ae3bf066075349b562..ea9128abe5995851968ad34412c6003895125f14 100644
--- a/webrtc/video/end_to_end_tests.cc
+++ b/webrtc/video/end_to_end_tests.cc
@@ -2641,7 +2641,8 @@ void EndToEndTest::VerifyHistogramStats(bool use_rtx,
 
   std::string video_prefix =
       screenshare ? "WebRTC.Video.Screenshare." : "WebRTC.Video.";
-
+  std::string video_prefix_sliced =
+      screenshare ? "WebRTC.Video.Screenshare.S0." : "WebRTC.Video.";
   // Verify that stats have been updated once.
   EXPECT_EQ(2, metrics::NumSamples("WebRTC.Call.LifetimeInSeconds"));
   EXPECT_EQ(1, metrics::NumSamples(
@@ -2703,10 +2704,13 @@ void EndToEndTest::VerifyHistogramStats(bool use_rtx,
   EXPECT_EQ(1, metrics::NumSamples("WebRTC.Video.CurrentDelayInMs"));
   EXPECT_EQ(1, metrics::NumSamples("WebRTC.Video.OnewayDelayInMs"));
 
-  EXPECT_EQ(1, metrics::NumSamples(video_prefix + "EndToEndDelayInMs"));
-  EXPECT_EQ(1, metrics::NumSamples(video_prefix + "EndToEndDelayMaxInMs"));
-  EXPECT_EQ(1, metrics::NumSamples(video_prefix + "InterframeDelayInMs"));
-  EXPECT_EQ(1, metrics::NumSamples(video_prefix + "InterframeDelayMaxInMs"));
+  EXPECT_EQ(1, metrics::NumSamples(video_prefix_sliced + "EndToEndDelayInMs"));
+  EXPECT_EQ(1,
+            metrics::NumSamples(video_prefix_sliced + "EndToEndDelayMaxInMs"));
+  EXPECT_EQ(1,
+            metrics::NumSamples(video_prefix_sliced + "InterframeDelayInMs"));
+  EXPECT_EQ(
+      1, metrics::NumSamples(video_prefix_sliced + "InterframeDelayMaxInMs"));
 
   EXPECT_EQ(1, metrics::NumSamples("WebRTC.Video.RenderSqrtPixelsPerSecond"));