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 a4d70336030da62f427db29e2aa20aeb7f3c8c5a..18affd07ce869614812cfece5b5e142c0933967a 100644
--- a/webrtc/video/end_to_end_tests.cc
+++ b/webrtc/video/end_to_end_tests.cc
@@ -2808,7 +2808,9 @@ void EndToEndTest::VerifyHistogramStats(bool use_rtx,
 
   std::string video_prefix =
       screenshare ? "WebRTC.Video.Screenshare." : "WebRTC.Video.";
-
+  // The content type extension is disabled in non screenshare test,
+  // therefore no slicing on simulcast id should be present.
+  std::string video_suffix = screenshare ? ".S0" : "";
   // Verify that stats have been updated once.
   EXPECT_EQ(2, metrics::NumSamples("WebRTC.Call.LifetimeInSeconds"));
   EXPECT_EQ(1, metrics::NumSamples(
@@ -2870,10 +2872,14 @@ 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 + "EndToEndDelayInMs" +
+                                   video_suffix));
+  EXPECT_EQ(1, metrics::NumSamples(video_prefix + "EndToEndDelayMaxInMs" +
+                                   video_suffix));
+  EXPECT_EQ(1, metrics::NumSamples(video_prefix + "InterframeDelayInMs" +
+                                   video_suffix));
+  EXPECT_EQ(1, metrics::NumSamples(video_prefix + "InterframeDelayMaxInMs" +
+                                   video_suffix));
 
   EXPECT_EQ(1, metrics::NumSamples("WebRTC.Video.RenderSqrtPixelsPerSecond"));