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 0fb7d917f1b94f971ee654d7adf0beeaa4a68e7f..eaf48ab3d5851fcf84584b20af983525d31b0331 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -594,6 +594,19 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="AppBanners.BeforeInstallEvent"
+    enum="AppBannersBeforeInstallEvent">
+  <owner>dominickn@chromium.org</owner>
+  <summary>
+    App banners promote an application related to the current website, and are
+    requested specifically through the current page's HTML.  This stat tracks
+    usage of the BeforeInstallPromptEvent, which allows developers to control
+    when an app banner appears. The events in this histogram are not mutually
+    exclusive - for example, preventDefault() must be called if prompt() is
+    called.
+  </summary>
+</histogram>
+
 <histogram name="AppBanners.DismissEvent" enum="AppBannersDismissEvent">
   <owner>dfalcantara@chromium.org</owner>
   <summary>
@@ -63097,6 +63110,15 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <int value="4" label="Undos Dismissed (Action) (Deprecated)"/>
 </enum>
 
+<enum name="AppBannersBeforeInstallEvent" type="int">
+  <int value="1" label="Event created and dispatched"/>
+  <int value="2" label="Showing the banner"/>
+  <int value="3" label="preventDefault() not called"/>
+  <int value="4" label="preventDefault() called"/>
+  <int value="5" label="prompt() called after preventDefault()"/>
+  <int value="6" label="prompt() not called after preventDefault()"/>
+</enum>
+
 <enum name="AppBannersDismissEvent" type="int">
   <int value="41" label="Error/unknown reason for dismissal"/>
   <int value="42" label="User opened the application after installing it"/>