Autoplay time metric

third_party/WebKit/Source/core/html/media/AutoplayUmaHelper.h

 // Copyright 2016 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 AutoplayUmaHelper_h
 #define AutoplayUmaHelper_h
 
 #include "core/CoreExport.h"
 #include "core/dom/ContextLifecycleObserver.h"
 #include "core/events/EventListener.h"
 #include "platform/heap/Handle.h"
+#include "public/platform/WebMediaPlayerClient.h"
 
 #include <set>
 
 namespace blink {
 
 // These values are used for histograms. Do not reorder.
 enum class AutoplaySource {
   // Autoplay comes from HTMLMediaElement `autoplay` attribute.
   kAttribute = 0,
   // Autoplay comes from `play()` method.
@@ skipping 58 matching lines @@
 
   bool IsVisible() const { return is_visible_; }
 
   bool HasSource() const { return !sources_.empty(); }
 
   DECLARE_VIRTUAL_TRACE();
 
  private:
   friend class MockAutoplayUmaHelper;
 
+  // Called when source is initialized and loading starts.
+  void OnLoadStarted();
+
   explicit AutoplayUmaHelper(HTMLMediaElement*);
   void handleEvent(ExecutionContext*, Event*) override;
   void HandlePlayingEvent();
   void HandlePauseEvent();
   virtual void HandleContextDestroyed();  // Make virtual for testing.
 
   void MaybeUnregisterContextDestroyedObserver();
   void MaybeUnregisterMediaElementPauseListener();
 
   void MaybeStartRecordingMutedVideoPlayMethodBecomeVisible();
   void MaybeStopRecordingMutedVideoPlayMethodBecomeVisible(bool is_visible);
 
   void MaybeStartRecordingMutedVideoOffscreenDuration();
   void MaybeStopRecordingMutedVideoOffscreenDuration();
 
   void MaybeRecordUserPausedAutoplayingCrossOriginVideo();
 
   void OnVisibilityChangedForMutedVideoOffscreenDuration(bool is_visibile);
   void OnVisibilityChangedForMutedVideoPlayMethodBecomeVisible(bool is_visible);
 
   bool ShouldListenToContextDestroyed() const;
   bool ShouldRecordUserPausedAutoplayingCrossOriginVideo() const;
 
   // The autoplay sources.
   std::set<AutoplaySource> sources_;
 
-  // The media element this UMA helper is attached to. |m_element| owns |this|.
+  // The media element this UMA helper is attached to. |element| owns |this|.
   Member<HTMLMediaElement> element_;
 
   // The observer is used to observe whether a muted video autoplaying by play()
   // method become visible at some point.
   // The UMA is pending for recording as long as this observer is non-null.
   Member<ElementVisibilityObserver>
       muted_video_play_method_visibility_observer_;
 
   // -----------------------------------------------------------------------
   // Variables used for recording the duration of autoplay muted video playing
   // offscreen.  The variables are valid when
-  // |m_autoplayOffscrenVisibilityObserver| is non-null.
+  // |autoplayOffscrenVisibilityObserver| is non-null.
   // The recording stops whenever the playback pauses or the page is unloaded.
 
   // The starting time of autoplaying muted video.
   int64_t muted_video_autoplay_offscreen_start_time_ms_;
 
   // The duration an autoplaying muted video has been in offscreen.
   int64_t muted_video_autoplay_offscreen_duration_ms_;
 
   // Whether an autoplaying muted video is visible.
   bool is_visible_;
 
   std::set<CrossOriginAutoplayResult> recorded_cross_origin_autoplay_results_;
 
   // The observer is used to observer an autoplaying muted video changing it's
   // visibility, which is used for offscreen duration UMA.  The UMA is pending
   // for recording as long as this observer is non-null.
   Member<ElementVisibilityObserver>
       muted_video_offscreen_duration_visibility_observer_;
+
+  double load_start_time_ms_;
 };
 
 }  // namespace blink
 
 #endif  // AutoplayUmaHelper_h