RTCPeerConnection.ontrack event added.

chrome/browser/media/webrtc/webrtc_browsertest_base.h

Index: chrome/browser/media/webrtc/webrtc_browsertest_base.h
diff --git a/chrome/browser/media/webrtc/webrtc_browsertest_base.h b/chrome/browser/media/webrtc/webrtc_browsertest_base.h
index 5c16feff67f26d07d9283baca27ddc3a0e6387b8..3eb9e18a2dee04e79305ba8d1664ea369f42cf4e 100644
--- a/chrome/browser/media/webrtc/webrtc_browsertest_base.h
+++ b/chrome/browser/media/webrtc/webrtc_browsertest_base.h
@@ -55,6 +55,15 @@ class WebRtcTestBase : public InProcessBrowserTest {
     INDIVIDUAL_STREAMS
   };
 
+  struct TrackEvent {
+    explicit TrackEvent(const std::string& track_id);
+    TrackEvent(const TrackEvent&);
+    ~TrackEvent();
+
+    std::string track_id;
+    std::vector<std::string> stream_ids;
+  };
+
  protected:
   WebRtcTestBase();
   ~WebRtcTestBase() override;
@@ -222,6 +231,8 @@ class WebRtcTestBase : public InProcessBrowserTest {
   bool HasReceiverWithTrack(content::WebContents* tab,
                             std::string track_id) const;
   size_t GetNegotiationNeededCount(content::WebContents* tab) const;
+  void SetupOnTrackListener(content::WebContents* tab) const;
+  std::vector<TrackEvent> GetTrackEvents(content::WebContents* tab) const;
 
  private:
   void CloseInfoBarInTab(content::WebContents* tab_contents,