Add webrtc metrics for video pause events to histograms.xml.

tools/metrics/histograms/histograms.xml

Index: tools/metrics/histograms/histograms.xml
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index 589b88cf8a0a8e62634695db17b413476e9157a3..f770e9631518ebac2638fc6d885e608d5facc9d3 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -73405,6 +73405,14 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="WebRTC.Video.NumberOfPauseEvents" units="pause events">
+  <owner>asapersson@chromium.org</owner>
+  <summary>
+    The number of times a video stream has been paused/resumed during a call.
+    Recorded when a stream is removed.
+  </summary>
+</histogram>
+
 <histogram name="WebRTC.Video.OnewayDelayInMs" units="ms">
   <owner>asapersson@chromium.org</owner>
   <summary>
@@ -73431,6 +73439,14 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="WebRTC.Video.PausedTimeInPercent" units="%">
+  <owner>asapersson@chromium.org</owner>
+  <summary>
+    Percentage of time that the video has been paused for a sent video stream.
+    Recorded when a stream is removed.
+  </summary>
+</histogram>
+
 <histogram name="WebRTC.Video.PliPacketsReceivedPerMinute"
     units="packets/minute">
   <owner>asapersson@chromium.org</owner>