RTCRtpSender with track behind RuntimeEnabled flag

chrome/browser/media/webrtc/webrtc_browsertest_base.cc

Index: chrome/browser/media/webrtc/webrtc_browsertest_base.cc
diff --git a/chrome/browser/media/webrtc/webrtc_browsertest_base.cc b/chrome/browser/media/webrtc/webrtc_browsertest_base.cc
index 23c2049420663e9176240a78663110a38d20f0f0..562ca644f58308216cd5b89fd62b6f097fb5b171 100644
--- a/chrome/browser/media/webrtc/webrtc_browsertest_base.cc
+++ b/chrome/browser/media/webrtc/webrtc_browsertest_base.cc
@@ -568,6 +568,16 @@ void WebRtcTestBase::CreateAndAddStreams(content::WebContents* tab,
           "createAndAddStreams(" + base::SizeTToString(count) + ")", tab));
 }
 
+void WebRtcTestBase::VerifyRtpSenders(
+    content::WebContents* tab,
+    base::Optional<size_t> expected_num_tracks) const {
+  std::string javascript =
+      expected_num_tracks ? "verifyRtpSenders(" +
+                                base::SizeTToString(*expected_num_tracks) + ")"
+                          : "verifyRtpSenders()";
+  EXPECT_EQ("ok-senders-verified", ExecuteJavascript(javascript, tab));
+}
+
 void WebRtcTestBase::VerifyRtpReceivers(
     content::WebContents* tab,
     base::Optional<size_t> expected_num_tracks) const {