Add a user action to capture opening a download.

Change-Id: I7afb93cd9c03195ff9de7f383e65e5ea69ff1c86
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2472958Reviewed-by: David Trainor <dtrainor@chromium.org>
Reviewed-by: Min Qin <qinmin@chromium.org>
Commit-Queue: Jesse Doherty <jwd@chromium.org>
Cr-Commit-Position: refs/heads/master@{#818510}

chrome/browser/download/download_stats.cc

@@ -5,6 +5,7 @@
 #include "chrome/browser/download/download_stats.h"
 
 #include "base/metrics/histogram_macros.h"
+#include "base/metrics/user_metrics.h"
 
 void RecordDownloadCount(ChromeDownloadCountTypes type) {
   UMA_HISTOGRAM_ENUMERATION(
@@ -29,6 +30,7 @@ void RecordOpenedDangerousConfirmDialog(
 }
 
 void RecordDownloadOpenMethod(ChromeDownloadOpenMethod open_method) {
+  base::RecordAction(base::UserMetricsAction("Download.Open"));
   UMA_HISTOGRAM_ENUMERATION("Download.OpenMethod",
                             open_method,
                             DOWNLOAD_OPEN_METHOD_LAST_ENTRY);

tools/metrics/actions/actions.xml

@@ -6103,6 +6103,18 @@ should be able to be added at any place in this file.
   </description>
 </action>
 
+<action name="Download.Open">
+  <owner>dtrainor@chromium.org</owner>
+  <owner>chrome-analysis-team@google.com</owner>
+  <description>
+    User opened a download. This action is logged every time the
+    Download.OpenMethod histogram is logged.
+
+    This histogram is of special interest to the chrome-analysis-team@. Do not
+    change its semantics or retire it without talking to them first.
+  </description>
+</action>
+
 <action name="DownloadNotification.Button_AlwaysOpenType">
   <owner>yoshiki@chromium.org</owner>
   <description>