Google Now Message Center Stats

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 a07ff11adc515b7bb7b1314027816e89e8a8761a..6c212ee6f1a70d6bc7b33d3e00500fc38a772329 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -7328,6 +7328,15 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   <summary>Events in Google Now component extension.</summary>
 </histogram>
 
+<histogram name="GoogleNow.MessageCenter.Displayed.NotificationsVisible"
+    units="count">
+  <owner>robliao@chromium.org</owner>
+  <owner>skare@chromium.org</owner>
+  <summary>
+    Count of the number of cards visible when the message center is shown.

[Ilya Sherman, 2014/05/05 23:27:36]

Which message center, btw?  Is the message center specific to Google Now, or is
it shared with other notifications?  If it's shared, is this counting just the
Google Now cards among the notifications?  Please clarify this in the summary
text.

[robliao, 2014/05/05 23:33:55]

There is no Google Now specific message center. There is only one message center
in Chrome. It is also known as the Notifications Center, but in code, it's
called the Message Center.
On 2014/05/05 23:27:36, Ilya Sherman wrote:

[Ilya Sherman, 2014/05/05 23:39:08]

Thanks.  Please update the summary text to clarify this.

On 2014/05/05 23:33:55, robliao wrote:

+  </summary>
+</histogram>
+
 <histogram name="GoogleUpdate.EffectivePolicy" enum="UpdatePolicy">
   <owner>gab@chromium.org</owner>
   <summary>