Record whether and why the media default controls are being shown.

third_party/WebKit/Source/core/html/HTMLMediaElement.h

 /*
  * Copyright (C) 2007, 2008, 2009, 2010, 2011, 2012, 2013 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 427 matching lines @@
     void removeUserGestureRequirement();
     void setInitialPlayWithoutUserGestures(bool);
 
     void setNetworkState(NetworkState);
 
     void audioTracksTimerFired(Timer<HTMLMediaElement>*);
 
     // TODO(liberato): remove once autoplay gesture override experiment concludes.
     void triggerAutoplayViewportCheckForTesting();
 
+    bool shouldShowControlsInternal(bool record) const;

[sof, 2016/02/18 16:12:17]

We prefer using enums rather bools in Blink.

[philipj_slow, 2016/02/19 04:05:43]

Yes, see `enum class RecordMetricsBehavior { DoNotRecord, DoRecord }`. If you do
that with a default argument, it should suffice to just keep
shouldShowControls(), with one place that passes DoRecord.

[mlamouri (slow - plz ping), 2016/02/23 18:42:13]

Re-used this enum. My understanding was that Chromium avoids default arguments
but I can see Blink doing this in a few places.

+
     UnthrottledTimer<HTMLMediaElement> m_loadTimer;
     UnthrottledTimer<HTMLMediaElement> m_progressEventTimer;
     UnthrottledTimer<HTMLMediaElement> m_playbackProgressTimer;
     UnthrottledTimer<HTMLMediaElement> m_audioTracksTimer;
     PersistentWillBeMember<TimeRanges> m_playedTimeRanges;
     OwnPtrWillBeMember<GenericEventQueue> m_asyncEventQueue;
 
     double m_playbackRate;
     double m_defaultPlaybackRate;
     NetworkState m_networkState;
@@ skipping 162 matching lines @@
 inline bool isHTMLMediaElement(const HTMLElement& element)
 {
     return isHTMLAudioElement(element) || isHTMLVideoElement(element);
 }
 
 DEFINE_HTMLELEMENT_TYPE_CASTS_WITH_FUNCTION(HTMLMediaElement);
 
 } // namespace blink
 
 #endif // HTMLMediaElement_h