Added new AutoplayEnabledThroughLoad entry to the Blink.MediaElement.Autoplay histogram

Source/core/html/HTMLMediaElement.cpp

 /*
  * 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 258 matching lines @@
 // These values are used for a histogram. Do not reorder.
 enum AutoplayMetrics {
     // Media element with autoplay seen.
     AutoplayMediaFound = 0,
     // Autoplay enabled and user stopped media play at any point.
     AutoplayStopped = 1,
     // Autoplay enabled but user bailed out on media play early.
     AutoplayBailout = 2,
     // Autoplay disabled but user manually started media.
     AutoplayManualStart = 3,
+    // Autoplay was (re)enabled through a user-gesture triggered load()
+    AutoplayEnabledThroughLoad = 4,
     // This enum value must be last.
     NumberOfAutoplayMetrics,
 };
 
 static void recordAutoplayMetric(AutoplayMetrics metric)
 {
     blink::Platform::current()->histogramEnumeration("Blink.MediaElement.Autoplay", metric, NumberOfAutoplayMetrics);
 }
 
 WebMimeRegistry::SupportsType HTMLMediaElement::supportsType(const ContentType& contentType, const String& keySystem)
@@ skipping 444 matching lines @@
 
     WTF_LOG(Media, "HTMLMediaElement::canPlayType(%p, %s, %s) -> %s", this, mimeType.utf8().data(), keySystem.utf8().data(), canPlay.utf8().data());
 
     return canPlay;
 }
 
 void HTMLMediaElement::load()
 {
     WTF_LOG(Media, "HTMLMediaElement::load(%p)", this);
 
-    if (UserGestureIndicator::processingUserGesture())
+    if (UserGestureIndicator::processingUserGesture()) {
+        recordAutoplayMetric(AutoplayEnabledThroughLoad);
         m_userGestureRequiredForPlay = false;
+    }
 
     prepareForLoad();
     loadInternal();
     prepareToPlay();
 }
 
 void HTMLMediaElement::prepareForLoad()
 {
     WTF_LOG(Media, "HTMLMediaElement::prepareForLoad(%p)", this);
 
@@ skipping 3342 matching lines @@
 
 #if ENABLE(WEB_AUDIO)
 void HTMLMediaElement::clearWeakMembers(Visitor* visitor)
 {
     if (!visitor->isAlive(m_audioSourceNode) && audioSourceProvider())
         audioSourceProvider()->setClient(nullptr);
 }
 #endif
 
 }