Add UMA histograms for HtmlVideoElementCapturerSource

content/renderer/media/html_video_element_capturer_source.cc

Index: content/renderer/media/html_video_element_capturer_source.cc
diff --git a/content/renderer/media/html_video_element_capturer_source.cc b/content/renderer/media/html_video_element_capturer_source.cc
index 293b9fe95e48098f84e202e5c3ea7483696f8e97..75744f8fb0c1d1bcf6110ac356bb5da1b1bdc46e 100644
--- a/content/renderer/media/html_video_element_capturer_source.cc
+++ b/content/renderer/media/html_video_element_capturer_source.cc
@@ -8,6 +8,7 @@
 #include "base/trace_event/trace_event.h"
 #include "content/public/renderer/render_thread.h"
 #include "content/renderer/media/media_stream_video_source.h"
+#include "content/renderer/media/webrtc_uma_histograms.h"
 #include "media/base/limits.h"
 #include "media/blink/webmediaplayer_impl.h"
 #include "third_party/WebKit/public/platform/WebMediaPlayer.h"
@@ -28,6 +29,10 @@ scoped_ptr<HtmlVideoElementCapturerSource>
 HtmlVideoElementCapturerSource::CreateFromWebMediaPlayerImpl(
     blink::WebMediaPlayer* player,
     const scoped_refptr<base::SingleThreadTaskRunner>& io_task_runner) {
+  // Save histogram data so we can see how much HTML Video capture is used.
+  // The histogram counts the number of calls to the JS API.
+  UpdateWebRTCMethodCount(WEBKIT_VIDEO_CAPTURE_STREAM);
+
   return make_scoped_ptr(new HtmlVideoElementCapturerSource(
       static_cast<media::WebMediaPlayerImpl*>(player)->AsWeakPtr(),
       io_task_runner));