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 543fa7e2cc5986675dd7fe8705bbb80713bfbfd2..81549ef90d15144fbcceb4e7e35dff8db2617b4e 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -38293,6 +38293,14 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="NewTabPage.ContentSuggestions.BackgroundFetchAge" units="ms">
+  <owner>markusheintz@chromium.org</owner>
+  <summary>
+    Android: The time passed between last successful background fetch of remote
+    content suggestions and displaying remote content suggestions to the user.

[Marc Treib, 2016/12/15 10:16:41]

nit: Since this doesn't directly correspond to a user action, the description
should mention when exactly it is recorded. How about something like:
Android: The time since the last successful background fetch of remote content
suggestions. Recorded when the user looks at content suggestions on the NTP.

[markusheintz_, 2016/12/15 12:42:07]

Thanks again a great suggestion. I find this easier to understand than mine. 

In general I think it does relate to a user action. The user pulling up the
remote suggestions list is the action that trigger recording the time since last
background fetch.

[Marc Treib, 2016/12/15 12:47:22]

It is triggered by a user action, but "TimeSinceLastBackgroundFetch" is not a
user action itself. That's why I insisted on a clear description :)

+  </summary>
+</histogram>
+
 <histogram name="NewTabPage.ContentSuggestions.CategoryDismissed"
     enum="ContentSuggestionsCategory">
   <owner>treib@chromium.org</owner>