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 bd67a34ae44f8197d34c54846d98b7755f42a1bf..c835b3501e126c8bbc510755174405141d42e659 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -58384,6 +58384,26 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="WebAudio.BiquadFilter.Q.Highpass">
+  <owner>rtoy@chromium.org</owner>
+  <owner>hongchan@chromium.org</owner>
+  <summary>
+    The Q value used for a highpass BiquadFilter.  Recorded each time the value
+    is set for a highpass filter via the .value setter or the automation methods
+    linearRampToValueAtTime, exponentialValueAtTime, and setValueAtTime.

[Mark P, 2016/05/06 23:58:34]

Is it appropriate to mix these automated methods with the .value setter method? 
i.e., is this mix of data from conceptually different sources useful?

[Raymond Toy, 2016/05/09 17:17:09]

I believe so.  These methods just automate what the user would have to do
manually to set Q values.  Ideally, we would want all Q values, but I think that
is too much data.  An automation method would produce 128 values every 3 ms or
so.  As a compromise, we just take the value given when the automation method is
called.  At least the user intended to use it at some time, even if it isn't
actually. (Automations are scheduled in the future and can be overridden or
cancelled.)

+  </summary>
+</histogram>
+
+<histogram name="WebAudio.BiquadFilter.Q.Lowpass">
+  <owner>rtoy@chromium.org</owner>
+  <owner>hongchan@chromium.org</owner>
+  <summary>
+    The Q value used for a lowpass BiquadFilter.  Recorded each time the value
+    is set for a lowpass filter via the .value setter or the automation methods
+    linearRampToValueAtTime, exponentialValueAtTime, and setValueAtTime.
+  </summary>
+</histogram>
+
 <histogram name="WebAudio.IIRFilterNode.Order">
   <owner>rtoy@chromium.org</owner>
   <owner>hongchan@chromium.org</owner>