Web Audio: record autoplay status when an AudioContext is destroyed.

tools/metrics/histograms/histograms.xml

Index: tools/metrics/histograms/histograms.xml
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index f08a4f286d91a22460c57f234cf4c468450a0859..d6a5f8a9327676adfc3282f9c20c13c04d5ea98d 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -68299,6 +68299,11 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="WebAudio.Autoplay.CrossOrigin" enum="WebAudioAutoplayStatus">
+  <owner>mlamouri@chromium.org</owner>
+  <summary>The autoplay status of an AudioContext when destroyed.</summary>
+</histogram>
+
 <histogram name="WebAudio.BiquadFilter.Q.Highpass">
   <owner>rtoy@chromium.org</owner>
   <owner>hongchan@chromium.org</owner>
@@ -102203,6 +102208,12 @@ value.
   <int value="3" label="Dismiss to open a newly installed WebAPK"/>
 </enum>
 
+<enum name="WebAudioAutoplayStatus" type="int">
+  <int value="0" label="The AudioContext failed to autoplay"/>
+  <int value="1" label="Failed to autoplay but start() called on user gesture"/>
+  <int value="2" label="The AudioContext successfully autoplayed"/>
+</enum>
+
 <enum name="WebBluetoothConnectGATTOutcome" type="int">
   <int value="0" label="Success"/>
   <int value="1" label="Device no longer in range"/>