Add support for single sample metrics.

content/renderer/media/render_media_log.cc

Index: content/renderer/media/render_media_log.cc
diff --git a/content/renderer/media/render_media_log.cc b/content/renderer/media/render_media_log.cc
index 1169f685b5a81ec6885ef39e92a8cb96195c0301..1fced0adcd057e4a0dd85f95f8eb64fb51805ee8 100644
--- a/content/renderer/media/render_media_log.cc
+++ b/content/renderer/media/render_media_log.cc
@@ -12,10 +12,12 @@
 #include "base/single_thread_task_runner.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "base/time/default_tick_clock.h"
+#include "content/common/metrics.mojom.h"
 #include "content/common/view_messages.h"
 #include "content/public/common/content_client.h"
 #include "content/public/renderer/content_renderer_client.h"
 #include "content/public/renderer/render_thread.h"
+#include "services/service_manager/public/cpp/interface_provider.h"
 
 #ifndef MEDIA_EVENT_LOG_UTILITY
 #define MEDIA_EVENT_LOG_UTILITY DVLOG(1)
@@ -50,6 +52,18 @@ RenderMediaLog::RenderMediaLog(const GURL& security_origin)
       ipc_send_pending_(false) {
   DCHECK(RenderThread::Get())
       << "RenderMediaLog must be constructed on the render thread";
+
+  mojom::OneShotMetricHostPtr one_shot_metric;

[bcwhite, 2017/02/21 12:37:54]

Why is the renderer accessing a "host" object?

[DaleCurtis, 2017/02/21 17:54:29]

Eh, it's just the naming scheme commonly used by mojo setups. I think XXXImpl is
also a common idiom that would make more sense here since each GetInterface()
call creates a new "host" side impl.

+  RenderThread::Get()->GetRemoteInterfaces()->GetInterface(&one_shot_metric);
+  one_shot_metric->Initialize("Media.UnderflowCount", 1, 100, 50);
+  one_shot_metric->SetSample(5);
+  one_shot_metric->SetSample(7);
+
+  mojom::OneShotMetricHostPtr one_shot_metric2;
+  RenderThread::Get()->GetRemoteInterfaces()->GetInterface(&one_shot_metric2);
+  one_shot_metric2->Initialize("Media.UnderflowCount", 1, 100, 50);
+  one_shot_metric2->SetSample(70);
+  one_shot_metric2->SetSample(100);
 }
 
 void RenderMediaLog::AddEvent(std::unique_ptr<media::MediaLogEvent> event) {