Revert "Measure whether muted videos that started playing with play() become visible at some point"

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

Index: third_party/WebKit/Source/core/html/HTMLMediaElement.h
diff --git a/third_party/WebKit/Source/core/html/HTMLMediaElement.h b/third_party/WebKit/Source/core/html/HTMLMediaElement.h
index f488f66e4074156da1c36a96c84e2f99d4642fb6..9863e39251d31afb640160653852f921101638df 100644
--- a/third_party/WebKit/Source/core/html/HTMLMediaElement.h
+++ b/third_party/WebKit/Source/core/html/HTMLMediaElement.h
@@ -46,7 +46,6 @@ namespace blink {
 
 class AudioSourceProviderClient;
 class AudioTrackList;
-class AutoplayUmaHelper;
 class ContentType;
 class CueTimeline;
 class ElementVisibilityObserver;
@@ -299,6 +298,13 @@ protected:
     void recordAutoplayMetric(AutoplayMetrics);
 
 private:
+    // These values are used for histograms. Do not reorder.
+    enum AutoplayUnmuteActionStatus {
+        AutoplayUnmuteActionFailure = 0,
+        AutoplayUnmuteActionSuccess = 1,
+        AutoplayUnmuteActionMax
+    };
+
     void resetMediaPlayerAndMediaSource();
 
     bool alwaysCreateUserAgentShadowRoot() const final { return true; }
@@ -493,6 +499,9 @@ private:
 
     EnumerationHistogram& showControlsHistogram() const;
 
+    void recordAutoplaySourceMetric(int source);
+    void recordAutoplayUnmuteStatus(AutoplayUnmuteActionStatus);
+
     void onVisibilityChangedForAutoplay(bool isVisible);
 
     UnthrottledTimer<HTMLMediaElement> m_loadTimer;
@@ -669,7 +678,6 @@ private:
 
     Member<AutoplayExperimentHelper::Client> m_autoplayHelperClient;
     Member<AutoplayExperimentHelper> m_autoplayHelper;
-    Member<AutoplayUmaHelper> m_autoplayUmaHelper;
 
     WebRemotePlaybackClient* m_remotePlaybackClient;