Record user interactions with MediaSession by action type

content/browser/media/session/media_session_uma_helper.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_BROWSER_MEDIA_SESSION_MEDIA_SESSION_UMA_HELPER_H_
 #define CONTENT_BROWSER_MEDIA_SESSION_MEDIA_SESSION_UMA_HELPER_H_
 
 #include <memory>
 
 #include "base/time/clock.h"
@@ skipping 11 matching lines @@
   // be appended only and must be added before |Count|.
   enum class MediaSessionSuspendedSource {
     SystemTransient = 0,
     SystemPermanent = 1,
     UI = 2,
     CONTENT = 3,
     SystemTransientDuck = 4,
     Count // Leave at the end.
   };
 
+  // Extended enum to blink::mojom::MediaSessionAction, distinguishing default
+  // action handling.
+  enum class MediaSessionUserAction {
+    Play = 0,
+    PlayDefault = 1,
+    Pause = 2,
+    PauseDefault = 3,
+    StopDefault = 4,
+    PreviousTrack = 5,
+    NextTrack = 6,
+    SeekBackward = 7,
+    SeekForward = 8,
+    Count  // Leave at the end.
+  };
+
   MediaSessionUmaHelper();
   ~MediaSessionUmaHelper();
 
   void RecordSessionSuspended(MediaSessionSuspendedSource source) const;
 
   // Record the result of calling the native requestAudioFocus().
   void RecordRequestAudioFocusResult(bool result) const;
 
+  void RecordMediaSessionUserAction(MediaSessionUserAction action) const;

[mlamouri (slow - plz ping), 2017/04/07 11:15:56]

Could that be static?

[Zhiqiang Zhang (Slow), 2017/04/07 15:12:43]

Done.

+
   void OnSessionActive();
   void OnSessionSuspended();
   void OnSessionInactive();
 
   void SetClockForTest(std::unique_ptr<base::TickClock> testing_clock);
 
  private:
   base::TimeDelta total_active_time_;
   base::TimeTicks current_active_time_;
   std::unique_ptr<base::TickClock> clock_;
 };
 
 }  // namespace content
 
 #endif // CONTENT_BROWSER_MEDIA_SESSION_MEDIA_SESSION_UMA_HELPER_H_